Effects of exercise and diet interventions on obesity-related sleep disorders in men: study protocol for a randomized controlled trial.

Abstract Background Sleep is essential for normal and healthy living. Lack of good quality sleep affects physical, mental and emotional functions. Currently, the treatments of obesity-related sleep disorders focus more on suppressing sleep-related symptoms pharmaceutically and are often accompanied by side effects. Thus, there is urgent need for alternative ways to combat chronic sleep disorders. This study will investigate underlying mechanisms of the effects of exercise and diet intervention on obesity-related sleep disorders, the role of gut microbiota in relation to poor quality of sleep and day-time sleepiness, as well as the levels of hormones responsible for sleep-wake cycle regulati…

Long-term leisure time physical activity and properties of bone: A twin study

Effects of physical activity on bone properties, when controlled for genetic effects, are not fully understood. We aimed to study the association between long-term leisure time physical activity (LTPA) and bone properties using twin pairs known to be discordant for leisure time physical activity for at least 30 yr. Volumetric BMD and geometric properties were measured at the tibia shaft and distal end using pQCT in 16 middle-aged (50-74 yr) same-sex twin pairs (seven monozygotic [MZ] and nine dizygotic [DZ] pairs) selected from a population-based cohort. Paired differences between active and inactive co-twins were studied. Active members of MZ twin pairs had larger cortical bone cross-secti…

EMG, muscle fibre and force production characteristics during a 1 year training period in elite weight-lifters.

The effects of a 1 year training period on 13 elite weight-lifters were investigated by periodical tests of electromyographic, muscle fibre and force production characteristics. A statistically non-significant increase of 3.5% in maximal isometric strength of the leg extensors, from 4841 +/- 1104 to 5010 +/- 1012 N, occurred over the year. Individual changes in the high force portions of the force-velocity curve correlated (p less than 0.05-0.01) with changes in weight-lifting performance. Training months 5-8 were characterized by the lowest average training intensity (77.1 +/- 2.0%), and this resulted in a significant (p less than 0.05) decrease in maximal neural activation (IEMG) of the m…

Hormone replacement therapy enhances IGF-1 signaling in skeletal muscle by diminishing miR-182 and miR-223 expressions : a study on postmenopausal monozygotic twin pairs

MiRNAs are fine-tuning modifiers of skeletal muscle regulation, but knowledge of their hormonal control is lacking. We used a co-twin case-control study design, that is, monozygotic postmenopausal twin pairs discordant for estrogen-based hormone replacement therapy (HRT) to explore estrogen-dependent skeletal muscle regulation via miRNAs. MiRNA profiles were determined from vastus lateralis muscle of nine healthy 54-62-years-old monozygotic female twin pairs discordant for HRT (median 7 years). MCF-7 cells, human myoblast cultures and mouse muscle experiments were used to confirm estrogen's causal role on the expression of specific miRNAs, their target mRNAs and proteins and finally the act…

Regular Strength and Sprint Training Counteracts Bone Aging: a 10- year Follow-up in Male Masters Athletes

According to cross-sectional and interventional studies, high-intensity strength and impact-type training provide a powerful osteogenic stimulus even in old age. Longitudinal evidence on the ability of high-intensity training to attenuate age-related bone deterioration is currently lacking, however. This follow-up study assessed the role of continued strength and sprint training on bone aging in 40- to 85-year-old male sprinters (n=69) with long-term training background. pQCT-derived bone structural, strength and densitometric parameters of the distal tibia (5% distal-proximal tibia length) and tibial midshaft (50% length) were assessed at baseline and after 10 years. The groups of well-tra…

Association of low 25-hydroxyvitamin D concentrations with elevated parathyroid hormone concentrations and low cortical bone density in early pubertal and prepubertal Finnish girls

Background: Very few studies have evaluated both parathyroid hormone (PTH) and 25-hydroxyvitamin D [25(OH)D] and their effects on bone mass in children. Objective: We studied the associations of serum 25(OH)D and intact PTH (iPTH) with bone mineral content (BMC) and bone mineral density (BMD) at different bone sites and the relation between serum 25(OH)D and iPTH in early pubertal and prepubertal Finnish girls. Design: The subjects were 10‐12-y-old girls (n = 193) at Tanner stage 1 or 2, who reported a mean (± SD) dietary calcium intake of 733 ± 288 mg/d. 25(OH)D, iPTH, tartrate-resistant acid phosphatase 5b (TRAP 5b), urinary calcium excretion, BMC, areal BMD, and volumetric BMD were asses…

Vertical jumping height and horizontal overhead throwing velocity in young male athletes

The purpose of this study was to examine the effects of calendar and skeletal age, anthropometric dimensions, training history and their interactions on vertical jumping height and horizontal overhead throwing velocity in a cross-section of 318 young male athletes (age range 9-16 years) participating in cross-country skiing (n = 70), basketball (n = 40), apparatus gymnastics (n = 19), ice hockey (n = 50), track and field (n = 89) and wrestling (n = 50). Vertical jumping height was measured with four different loads held on the shoulders and then interpolated for loads representing 0 and 40% body mass. Horizontal overhead throwing velocity using both hands was determined for seven balls of d…

Daily hormonal and neuromuscular responses to intensive strength training in 1 week.

Daily adaptive responses in the neuromuscular and endocrine systems to a 1-week very intensive strength training period with two training sessions per day were investigated in eight elite weight lifters. The morning and the afternoon sessions resulted in acute decreases (P less than 0.05-0.01) in maximal isometric strength and in the maximal neural activation (iEMG) of the leg extensor muscles, but the basic levels remained unaltered during the entire training period. Significant (P less than 0.05-0.01) acute increases in serum total and free testosterone levels were found during the afternoon sessions. During the 1-week training period, serum total and free testosterone concentrations decr…

Shared Genetic and Environmental Effects on Strength and Power in Older Female Twins

Purpose: This study examined the relative contribution of genetic and environmental effects on maximal leg extensor power and also investigated whether leg extensor power and maximum voluntary isometric knee extensor strength share a genetic component. Methods: Muscle functions were measured as part of the Finnish Twin Study on Aging in 101 monozygotic (MZ) and 116 dizygotic (DZ) female twin pairs aged 63–76 yr. Leg extensor power was measured using the Nottingham Leg Extensor Power Rig and maximum voluntary isometric knee extensor strength using an adjustable dynamometer chair. The analyses were carried out using the maximum likelihood method in Mx-program on the raw data set. Results: A b…

Strength, [corrected] endurance or combined training elicit diverse skeletal muscle myosin heavy chain isoform proportion but unaltered androgen receptor concentration in older men.

We investigated whether the myosin heavy chain (MyHC) proportion and androgen receptor (AR) concentration in skeletal muscle differ following 21 weeks of strength, endurance and combined training in untrained older men. Strength (S) and endurance (E) groups trained twice per week and combined (S+E) group trained four times per week (two strength and two endurance). Muscle biopsies were obtained before and after the training period from m. vastus lateralis (VL) and AR mRNA and protein concentration and MyHC proportion were determined. 1RM increased during the training period in S, S+E and E but the changes were greater in S and S+E than in E. Statistically significant increases were observed…

Contribution of genetic and environmental factors to individual differences in maximal walking speed with and without second task in older women

Background. Among older people, distraction while walking may increase the risk of falls. Factors underlying individual differences in dual tasking are not fully understood. Our aim was to study the effect of a second task on maximal walking speed and to examine whether individual differences in walking speed measured with and without a second task are accounted for by genetic and environmental influences shared across tasks or specific to each task. Methods. The data were collected from the 101 monozygotic and 116 dizygotic twin pairs aged 63–76 years recruited from the Finnish Twin Cohort. Maximal walking speed (MWS) over 10 m was measured on a laboratory corridor and timed with photocell…

Effects of a low-frequency sound wave therapy programme on functional capacity, blood circulation and bone metabolism in frail old men and women

Objective: To evaluate the effects of a low-frequency sound wave therapy programme on functional capacity, blood circulation and bone metabolism of the frail elderly. Design: Single-blind, randomized, controlled trial. Setting: Two senior service centres. Subjects: Forty-nine volunteers (14 males and 35 females) aged 62—93 years with up to 12 diagnosed diseases were allocated in either the intervention group (n = 30) or control group (n = 19). Intervention: The intervention group underwent sound wave therapy, 3—5 times a week for 30 minutes per session over a period of 6 months. The control group received no intervention. Main measurements: Blood pressure, functional capacity, mobility, bo…

Growth patterns at distal radius and tibial shaft in pubertal girls: a 2-year longitudinal study.

Bone changes, in terms of both size and BMD, were assessed longitudinally in pubertal girls. Before puberty, BMD at the distal radius declined, whereas bone size increased, suggesting that normal growing girls experience a transient period of increased bone fragility. This could explain the elevated low-trauma forearm fracture rates reported in earlier studies. Introduction: Longitudinal data on bone growth during puberty are sparse. Such information is needed to understand the sequence of biological changes, the physical and mechanical consequences for the growing skeleton, and the implications for later life. Materials and Methods: The geometric properties and volumetric BMD (vBMD) of the…

Serum hormones during prolonged training of neuromuscular performance.

The effects of a 24-weeks' progressive training of neuromuscular performance capacity on maximal strength and on hormone balance were investigated periodically in 21 male subjects during the course of the training and during a subsequent detraining period of 12 weeks. Great increases in maximal strength were noted during the first 20 weeks, followed by a plateau phase during the last 4 weeks of training. Testosterone/cortisol ratio increased during training. During the last 4 weeks of training changes in maximal strength correlated with the changes in testosterone/cortisol (P less than 0.01) and testosterone/SHBG (P less than 0.05) ratios. During detraining, correlative decreases were found…

Muscle hypertrophy, hormonal adaptations and strength development during strength training in strength-trained and untrained men.

Hormonal and neuromuscular adaptations to strength training were studied in eight male strength athletes (SA) and eight non-strength athletes (NA). The experimental design comprised a 21-week strength-training period. Basal hormonal concentrations of serum total testosterone (T), free testosterone (FT) and cortisol (C) and maximal isometric strength, right leg 1 repetition maximum (RM) of the leg extensors were measured at weeks 0, 7, 14 and 21. Muscle cross-sectional area (CSA) of the quadriceps femoris was measured by magnetic resonance imaging (MRI) at weeks 0 and 21. In addition, the acute heavy resistance exercises (AHRE) (bilateral leg extension, five sets of ten RM, with a 2-min rest…

Genetic effects in common on maximal walking speed and muscle performance in older women

The purpose was to examine whether maximal walking speed, maximal isometric knee extensor strength, and leg extensor power share genetic or environmental effects in common. The data was collected from 103 monozygotic and 114 dizygotic female twin pairs aged 63–76 years. Maximal walking speed over 10 m was measured in the laboratory corridor using photocells for timing. Isometric knee extensor strength and leg extensor power were measured using an adjustable dynamometer. The genetic models showed that strength, power, and walking speed had a genetic effect in common which accounted for 52% of the variance in strength, 36% in power, and 34% in walking speed. Strength and power had a non-share…

Walking Ability and All-Cause Mortality in Older Women

In this study self-reported ability to walk 2 km and six-minute walking test (6MWT) performance were examined as predictors of all-cause mortality in 434 women, aged 63-76 years. The primary outcome measure was all-cause mortality (follow-up: 8 years). Predictors were self-reported difficulties in walking 2 km and 6-min walking distance tertiles of ≤495, 496-560 and ≥561 m, and no test result due to refusal by the physician to grant permission to perform the test or participant's inability or unwillingness to perform the test. During the follow-up, 39 participants died. Participants reporting minor (age- and body mass index-adjusted hazard ratio 2.53, 95% confidence interval 1.12-5.69) or m…

Trait-specific tracking and determinants of body composition: a 7-year follow-up study of pubertal growth in girls

Abstract Background Understanding how bone (BM), lean (LM) and fat mass (FM) develop through childhood, puberty and adolescence is vital since it holds key information regarding current and future health. Our study aimed to determine how BM, LM and FM track from prepuberty to early adulthood in girls and what factors are associated with intra- and inter-individual variation in these three tissues. Methods The study was a 7-year longitudinal cohort study. BM, LM and FM measured using dual-energy X-ray absorptiometry, self-reported dietary information, leisure time physical activity (LTPA) and other factors were assessed one to eight times in 396 girls aged 10 to 13 years (baseline), and in 2…

Hormone therapy is associated with better body composition and adipokine/glucose profiles

Objective: The aim of this study was to evaluate the possibility of preventing the metabolic health consequences of postmenopausal hypogonadism with the use of long-term hormone therapy (HT). Methods: We used a monozygotic co-twin control design including 10 twin pairs (aged 56-62 y) discordant for HT (duration of HT, 2-10 y). In addition, 14 premenopausal women (aged 29-35 y) who did not use HT were studied to evaluate the differences in metabolic health between the premenopausal and postmenopausal states. Body composition was determined, and waist-to-hip ratio was used as an estimate for fat distribution. Serum sex steroids, sex hormone-binding globulin, and serum lipid and glucose profil…

Serum osteocalcin is not associated with glucose but is inversely associated with leptin across generations of nondiabetic women.

The skeleton is recognized as an important player in energy metabolism through its interactions with other tissues. Whether the association of osteocalcin with glucose metabolism is age dependent has not been fully addressed.The objective of the study was to examine the age-specific association between different forms of osteocalcin and glucose and adipokines.This was a family-based study across three generations.The study was conducted at a university laboratory.Sixty-four daughter-premenopausal mother-maternal grandmother trios participated in the study.Fasting plasma glucose and insulin concentrations, serum total (tOC), carboxylated (cOC), and uncarboxylated (ucOC = tOC - cOC) osteocalc…

Estrogen receptor alpha polymorphism modifies the association between childhood exercise and bone mass: follow-up study.

This follow-up study confirms our previous findings that the ER-α PvuII polymorphism (Pp) modulates the association between exercise and bone mass. The differences in bone properties of girls with consistently low physical activity (LLPA) and consistently high physical activity (HHPA) were evident only in those bearing the heterozygote ER-α genotype (Pp). In particular, areal bone mineral density of the total femur, bone mineral content and areal bone mineral density of the femoral neck, and bone mineral content and cortical thickness of the tibia shaft were significantly (p < .05) lower in the Pp girls with LLPA than in their HHPA counterparts. These findings might partly explain the ge…

Promoting safe walking among older people : the effects of a physical and cognitive training intervention vs. physical training alone on mobility and falls among older community-dwelling men and women (the PASSWORD study): design and methods of a randomized controlled trial

Abstract Background Safe and stable walking is a complex process involving the interaction of neuromuscular, sensory and cognitive functions. As physical and cognitive functions deteriorate with ageing, training of both functions may have more beneficial effects on walking and falls prevention than either alone. This article describes the study design, recruitment strategies and interventions of the PASSWORD study investigating whether a combination of physical and cognitive training (PTCT) has greater effects on walking speed, dual-task cost in walking speed, fall incidence and executive functions compared to physical training (PT) alone among 70–85-year-old community-dwelling sedentary or…

Neuromuscular and hormonal adaptations in athletes to strength training in two years.

Neuromuscular and hormonal adaptations to prolonged strength training were investigated in nine elite weight lifters. The average increases occurred over the 2-yr follow-up period in the maximal neural activation (integrated electromyogram, IEMG; 4.2%, P = NS), maximal isometric leg-extension force (4.9%, P = NS), averaged concentric power index (4.1%, P = NS), total weight-lifting result (2.8%, P less than 0.05), and total mean fiber area (5.9%, P = NS) of the vastus lateralis muscle, respectively. The training period resulted in increases in the concentrations of serum testosterone from 19.8 +/- 5.3 to 25.1 +/- 5.2 nmol/l (P less than 0.05), luteinizing hormone (LH) from 8.6 +/- 0.8 to 9…

Does Serum 25-Hydroxyvitamin D Influence Muscle Development during Puberty in Girls? - A 7-Year Longitudinal Study

Vitamin D is well known for its regulatory role in calcium and phosphate homeostasis, but its role in muscle mass and strength during growth remains inconclusive. We explored the association of serum 25-hydroxyvitamin D (25(OH)D) with muscle development in girls from 11 to 18-years old. Whole body lean tissue mass (LMWB), appendicular lean mass (aLM), muscle cross-sectional area at the lower leg (mCSA), maximal voluntary contraction of elbow flexors (MVC elbow) and knee extensors (MVC knee) were assessed in 217 girls aged 10-13 years (at baseline), 215 in 2-year and 226 in 7.5-year follow-up. Serum concentration of 25(OH)D and intact parathyroid hormone (PTH) were analyzed retrospectively a…

Recovery after Heavy Resistance Exercise and Skeletal Muscle Androgen Receptor and Insulin-Like Growth Factor-I Isoform Expression in Strength Trained Men

The effects of heavy resistance exercise on skeletal muscle androgen receptor (AR) protein concentration and mRNAs of AR, insulin-like growth factor-I (IGF)-IEa, and mechano growth factor (MGF) expression were examined from biopsies of vastus lateralis (VL) muscle before and 48 hours after heavy resistance exercise (5 × 10 repetition maximum [RM] leg press and 4 × 10RM squats) in 8 adult strength trained men. The present exercise induced an acute decrease in maximal isometric force and increased serum total testosterone (T) and free testosterone (FT) concentrations. During 2 recovery days, maximal isometric force and subjective perception of physical fitness remained significantly lowered, …

Assessing body composition with DXA and bioimpedance: effects of obesity, physical activity, and age.

Objective: This study evaluated to what extent dual-energy X-ray absorptiometry (DXA) and two types of bioimpedance analysis (BIA) yield similar results for body fat mass (FM) in men and women with different levels of obesity and physical activity (PA). Methods and Procedures: The study population consisted of 37–81-year-old Finnish people (82 men and 86 women). FM% was estimated using DXA (GE Lunar Prodigy) and two BIA devices (InBody (720) and Tanita BC 418 MA). Subjects were divided into normal, overweight, and obese groups on the basis of clinical cutoff points of BMI, and into low PA (LPA) and high PA (HPA) groups. Agreement between the devices was calculated by using the Bland–Altman …

COL1A1 Sp1 polymorphism associates with bone density in early puberty.

Optimal acquisition of bone mass in puberty is a key determinant of the lifetime risk of osteoporosis and has a strong genetic basis. We investigated the relationship between the COL1A1 Sp1 polymorphism and BMD in early puberty, and how the genotypes relate to bone size and geometry as well as bone turnover and material properties in 247 10- to 13-year-old girls. Bone properties were measured using DXA, pQCT, and ultrasound. Also, serum P1NP, OC, B-ALP, and TRACP 5b were assessed. Our results showed that girls with the TT genotype had significantly lower BMC and BMD of the total body, lumbar spine, and proximal femur, as well as BUA at the calcaneus, than those with the GT and GG genotype. …

Dietary Intake, Serum Hormones, Muscle Mass and Strength During Strength Training in 49 - 73-Year-Old Men

Effects of dietary intake on serum hormones, muscle cross-sectional area (CSA) and strength during strength training were studied in two groups of men: 1) strength training + nutritional counseling (n = 22, 59.1 +/- 6.1 yrs), and 2) strength training (n = 23, 58.5 +/- 7.1 yrs). Both groups performed strength training twice a week for 21 weeks. Counseling increased carbohydrate (p < 0.01) and fiber intake (p < 0.001) and polyunsaturated/saturated fat-ratio (p < 0.05) and decreased fat intake (p < 0.01). Muscle strength and CSA increased by 16 - 20 % and by 5.4 - 5.9 % in both groups (p < 0.001). Changes in protein content of diet correlated with the changes in the acute postexercise concentr…

ASYMMETRICAL LOWER EXTREMITY POWER DEFICIT AS A RISK FACTOR FOR INJURIOUS FALLS IN HEALTHY OLDER WOMEN

Effects of resistance training on expression of IGF-I splice variants in younger and older men.

Insulin-like growth factor-I (IGF-I) and its splice variants Insulin-like growth factor-I isoform Ea (IGF-IEa) and mechano growth factor (MGF) may play an important role in muscular adaptations to resistance training (RT) that may be modulated by ageing. It has been suggested that IGF-I induces cellular responses via AKT8 virus oncogene cellular homolog (Akt) and Extracellular signal-regulated kinase (Erk) signalling pathways. Therefore, resistance exercise-induced changes in skeletal muscle IGF-IEa and MGF messenger ribonucleic acid (mRNA), and MGF, Erk1/2, Akt and p70S6K protein expression were investigated before and after 21 weeks of RT in younger (YM, 20–34 yrs., n = 7) and older men (…

Associations of physical activity in detailed intensity ranges with body composition and physical function : a cross-sectional study among sedentary older adults

Background Physical activity is crucial to maintain older adults’ health and functioning, but the health benefits of particular activity intensities remain unclear. The aim of this cross-sectional study was to peruse the distribution of physical activity, and to investigate the associations of particular physical activity intensities with body composition and physical function among older adults. Methods The sample comprised of 293 community-dwelling sedentary or at most moderately active older adults (42% men, mean age 74 ± 4 years). Physical activity was measured with a hip-worn tri-axial accelerometer over seven consecutive days, and investigated in detailed intensity range and in catego…

Interactive effects of aging and aerobic capacity on energy metabolism-related metabolites of serum, skeletal muscle, and white adipose tissue

ABSTRACTAerobic capacity is a strong predictor of longevity. With aging, aerobic capacity decreases concomitantly with changes in whole body metabolism leading to increased disease risk. To address the role of aerobic capacity, aging and their interaction on metabolism, we utilized rat models of low and high intrinsic aerobic capacity (LCRs/HCRs) and assessed the metabolomics of serum, muscle, and white adipose tissue (WAT). We compared LCRs and HCRs at two time points: Young rats were sacrificed at 9 months, and old rats were sacrificed at 21 months. Targeted and semi-quantitative metabolomics analysis was performed on ultra-pressure Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS)…

DIFFERENTIAL INFLUENCE OF PERIPHERAL AND SYSTEMIC SEX STEROIDS ON SKELETAL MUSCLE QUALITY IN PRE- AND POSTMENOPAUSAL WOMEN.

Aging is associated with gradual decline of skeletal muscle strength and mass often leading to diminished muscle quality. This phenomenon is known as sarcopenia and affects about 30% of the over 60-year-old population. Androgens act as anabolic agents regulating muscle mass and improving muscle performance. The role of female sex steroids as well as the ability of skeletal muscle tissue to locally produce sex steroids has been less extensively studied. We show that despite the extensive systemic deficit of sex steroid hormones in postmenopausal compared to premenopausal women, the hormone content of skeletal muscle does not follow the same trend. In contrast to the systemic levels, muscle t…

The effects of a physical and cognitive training intervention vs. physical training alone on older adults' physical activity : A randomized controlled trial with extended follow-up during COVID-19

BackgroundExecutive functions underlie self-regulation and are thus important for physical activity and adaptation to new situations. The aim was to investigate, if yearlong physical and cognitive training (PTCT) had greater effects on physical activity among older adults than physical training (PT) alone, and if executive functions predicted physical activity at baseline, after six (6m) and twelve months (12m) of the interventions, one-year post-intervention follow-up and an extended follow-up during COVID-19 lockdown.MethodsData from a single-blinded, parallel-group randomized controlled trial (PASSWORD-study, ISRCTN52388040) were utilized. Participants were 70-85 years old community-dwel…

Women With and Without Metabolic Disorder Differ in Their Gut Microbiota Composition

The aim of this study was to investigate whether overweight/obese women in metabolic disorder group (MDG, n = 27) differ in their gut microbiota composition from overweight/obese women in non-metabolic disorder group (NMDG, n = 47) and normal weight women group (NWG, n = 11). Gut microbiota was profiled from fecal samples by 16S rRNA fluorescence in situ hybridization and flow cytometry in 85 premenopausal women. Body composition was measured by bioimpedance, and dietary intakes were collected via food diaries. Standard procedures were used to assess plasma glucose, serum insulin, lipids, and inflammatory status. We found that the proportion of bacteria belonging to Eubacterium rectale-Clos…

Type of surgery is associated with pain and walking difficulties among older people with previous hip fracture

Aim The aim was to assess the level of lower body pain among people with previous femoral neck fracture, and whether the type of surgery was associated with pain and physical function a mean of 2 years after surgery. Methods The study included 115 community-dwelling older adults aged 60 years and older with previous femoral neck fracture, and 31 reference subjects without previous lower limb injuries. A total of 30 patients had internal fixation surgery, 70 had hemiarthroplasty and 15 had total hip replacement. All patients had surgery in the same hospital and received typical inpatient rehabilitation. From 1.6 months to 7.5 years after the fracture, the patients underwent examination inclu…

Muscle hypertrophy, strength development, and serum hormones during strength training in elderly women with fibromyalgia.

To examine the effects of strength training on maximal force, cross-sectional area (CSA), and electromyographic (EMG) activity of muscles and serum hormone concentrations in elderly females with fibromyalgia (FM).Twenty-six patients with FM were randomly assigned to a training (FMT; n = 13; mean age 60 years) or a control (FMC; n = 13; 59 years) group. FMT performed progressive strength training twice a week for 21 weeks. The measurements included maximal isometric and concentric leg extension forces, EMG activity of the vastus lateralis and medialis, CSA of the quadriceps femoris, and serum concentrations of testosterone (T), free testosterone (FT), growth hormone (GH), insulin-like growth…

Serum basal hormone concentrations and muscle mass in aging women: Effects of strength training and diet

This study examined the effects of strength training and diet on serum basal hormone concentrations and muscle mass in aging women. Fifty-one women age 49 to 74 y were divided into two groups: strength training and nutritional counseling (n = 25), and strength training (n = 26). Both groups performed strength training twice a week for 21 wk. Nutritional counseling was given to attain sufficient energy and protein intake and recommended intake of fat and fiber. We found that the cross-sectional area of the quadriceps femoris increased by 9.5 ± 4.1% in the nutritional counseling group versus 6.8 ± 3.5% in the strength training only group after training (P &lt; 0.052). Nutritional counseling e…

Bone and body segment lengthening and widening: a 7-year follow-up study in pubertal girls.

Abstract During growth bone increases in length and width as does the body size. The aim of this paper was to examine the growth pattern of body height and weight, and the width and length of various body segments, and to establish the timing of peak growth velocity (PV) in relation to time of menarche in a cohort of Finnish girls followed from age 10 until 18. The study was a 7-year longitudinal cohort study. Widths and lengths of body segments and bones were measured from DXA scan images using bone landmarks in 396 girls aged 10 to 13 years at baseline, and in 255 mothers and 159 grandmothers. The girls' growth velocities (rate of change with time) peaked at 13.5 months prior to menarche …

Bone Density, Structure and Strength, and Their Determinants in Aging Sprint Athletes

This study was undertaken to examine bone properties in masters sprinters of different ages and younger reference subjects. In addition, the association of sport-specific ground reaction force, muscle, training, and hormone characteristics with the bone parameters was evaluated in the athletes.Bone densitometric, structural, and strength parameters were assessed by peripheral quantitative computed tomography at the distal and midtibia in 83 male sprinters (40-85 yr) and 19 physically active referents (31-45 yr). Between-group differences were analyzed by ANCOVA with body mass and height as covariates.Bone values were generally greater in athletes than referents, the greatest differences bei…

Serum Amino Acid Profiles in Childhood Predict Triglyceride Level in Adulthood: A 7-Year Longitudinal Study in Girls.

AbstractContext:Branched-chain and aromatic amino acids are associated with high risk of developing dyslipidemia and type II diabetes in adults.Objective:This study aimed to examine whether serum amino acid profiles associate with triglyceride concentrations during pubertal growth and predict hypertriglyceridemia in early adulthood.Design:This was a 7.5-year longitudinal study.Setting:The study was conducted at the Health Science Laboratory, University of Jyväskylä.Participants:A total of 396 nondiabetic Finnish girls aged 11.2 ± 0.8 years at the baseline participated in the study.Main Outcome Measures:Body composition was assessed by dual-energy x-ray absorptiometry; serum concentrations o…

Effects of 32-year leisure time physical activity discordance in twin pairs on health (TWINACTIVE study): aims, design and results for physical fitness.

AbstractThe physically active lifestyle is associated with low future morbidity and mortality, but the causality between physical activity and health is not always clear. As some inherited biological characteristics and childhood experiences may cause selection bias in observational studies, we sought to take them into account by identifying 16 twin pairs (7 MZ, 9 DZ, mean age 60 years) discordant for leisure time physical activity habits for thirty years. We conducted detailed health-related examinations among these twin pairs. Our main aims were to study the effects of physical activity and genes on fitness and body composition, with special reference to body fat compartments, metabolic s…

Hormone replacement therapy improves contractile function and myonuclear organization of single muscle fibres from postmenopausal monozygotic female twin pairs

Ageing is associated with a decline in muscle mass and strength leading to increased physical dependency in old age. Postmenopausal women experience a greater decline than men of similar age in parallel with the decrease in female sex steroid hormone production. We recruited six monozygous female twin pairs (55-59 years old) where only one twin pair was on hormone replacement therapy (HRT use = 7.8 ± 4.3 years) to investigate the association of HRT with the cytoplasmic volume supported by individual myonuclei (myonuclear domain (MND) size,) together with specific force at the single fibre level. HRT use was associated with a significantly smaller (∼27%; P < 0.05) mean MND size in muscle fib…

Electrocardiographic Indices of Left Ventricular Hypertrophy and Repolarization Phase Share the Same Genetic Influences: A Twin Study

Background: Both left ventricular hypertrophy (LVH) and repolarization phase (RP) are known to be attributable to genetic influences, but less is known whether they share same genetic influences. The aim of this study was to investigate to what extent individual differences in electrocardiographic (ECG) LVH and RP are explained by genetic and environmental influences and whether these influences are shared between these two traits. Methods: Resting ECG recordings were obtained from 186 monozygotic and 203 dizygotic female twin individuals, aged 63 to 76 years. Latent factors, called LVH and RP, were formed to condense the information obtained from LVH indices (Cornell voltage and Cornell pr…

Declining Physical Performance Associates with Serum FasL, miR-21, and miR-146a in Aging Sprinters.

Aging is associated with systemic inflammation and cellular apoptosis accelerating physiological dysfunctions. Whether physically active way of life affects these associations is unclear. This study measured the levels of serum inflammatory and apoptotic molecules, their change over 10 years, and their associations with physical performance in sprint-trained male athletes. HsCRP, cell counts, HGB, FasL, miR-21, and miR-146a were measured cross-sectionally (n=67, 18–90 yrs) and serum FasL, miR-21, and miR-146a and their aging-related associations with physical performance were assessed over a 10-year follow-up (n=49, 50–90 yrs). The cross-sectional study showed positive age correlations for …

Bone’s Structural Diversity in Adult Females Is Established before Puberty

Bone must be rigid for leverage yet light for mobility. We studied how bone modeling and remodeling fashioned differences in bone size, shape, and mass during growth to achieve these properties in adulthood.We measured the structural features of a tibial cross-section using quantitative computed tomography and markers of remodeling in 258 10- to 13-yr-old girls during 2 yr and in 108 of their mothers.Tibia total cross-sectional area and mass correlated between daughters and their mothers (r = 0.34 and 0.44, respectively, both P0.01). The location of a daughter's tibial total cross-sectional area, medullar area, and bone mass in the lower, middle, or upper part of the sample distribution was…

Corrigendum to “Low volumetric BMD is linked to upper-limb fracture in pubertal girls and persists into adulthood: A seven-year cohort study” [Bone 45 (2009) 480-486]

a Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland b Department of Orthopaedics and Traumatology, Kuopio University Hospital, Kuopio, Finland c Department of Preventive Medicine, University of Tennessee Health Science Center, USA d Endocrine Centre, Heidelberg Repatriation Hospital, Austin Health/Department of Medicine, University of Melbourne, Australia e Department of Medical Rehabilitation, Oulu University Hospital and Institute of Health Sciences, University of Oulu, Oulu, Finland

Maximal force, force/time and activation/coactivation characteristics of the neck muscles in extension and flexion in healthy men and women at different ages

This study examined the force production characteristics, activation/coactivation and endurance capacity of the neck extension and flexion muscles in healthy men (n=29) and women (n=28) divided into three age groups (18–26 years, 30–37 years and 45–55 years). Force and electromyography (EMG) measurements were performed during the maximal voluntary isometric extension and flexion actions. This was followed by an endurance test (ET; 60% force level of maximal voluntary contraction sustained until exhaustion), after which the force and EMG recordings were repeated. Men were both stronger and had higher values (P<0.001) for explosive force (rate of force development, RFD) than women in both act…

BMI and an anthropometry-based estimate of fat mass percentage are both valid discriminators of cardiometabolic risk: A comparison with DXA and bioimpedance

Objective. To determine whether categories of obesity based on BMI and an anthropometry-based estimate of fat mass percentage (FM% equation) have similar discriminative ability for markers of cardiometabolic risk as measurements of FM% by dual-energy X-ray absorptiometry (DXA) or bioimpedance analysis (BIA).Design and Methods. A study of 40–79-year-old male (n=205) and female (n=388) Finns. Weight, height, blood pressure, triacylglycerols, HDL cholesterol, and fasting blood glucose were measured. Body composition was assessed by DXA and BIA and a FM%-equation.Results. For grade 1 hypertension, dyslipidaemia, and impaired fasting glucose &gt;6.1 mmol/L, the categories of obesity as defined b…

Insulin resistance is associated with altered amino acid metabolism and adipose tissue dysfunction in normoglycemic women

AbstractInsulin resistance is associated adiposity, but the mechanisms are not fully understood. In this study, we aimed to identify early metabolic alterations associated with insulin resistance in normoglycemic women with varying degree of adiposity. One-hundred and ten young and middle-aged women were divided into low and high IR groups based on their median HOMA-IR (0.9 ± 0.4 vs. 2.8 ± 1.2). Body composition was assessed using DXA, skeletal muscle and liver fat by proton magnetic resonance spectroscopy, serum metabolites by nuclear magnetic resonance spectroscopy and adipose tissue and skeletal muscle gene expression by microarrays. High HOMA-IR subjects had higher serum branched-chain …

Monitoring bone growth using quantitative ultrasound in comparison with DXA and pQCT.

Quantitative ultrasound (QUS) is a safe, inexpensive, and nonradiation method for bone density assessment. QUS correlates with, and predicts fragility fractures comparable to, dual-energy X-ray absorptiometry (DXA)-derived bone mineral density (BMD) in postmenopausal women. However, its validity in monitoring bone growth in children is not well understood. Two hundred and fifty-eight 10-13 yr pubertal girls and 9 37-43 yr adults without diseases or history of medications known to affect bone metabolism were included in the 2-yr prospective study. Calcaneal broadband ultrasound attenuation (cBUA) was assessed using QUS-2 (Quidel, Santa Clara, CA), speed of sound of tibial shaft (tSOS) using …

Is bone loss the reversal of bone accrual? Evidence from a cross-sectional study in daughter-mother-grandmother trios.

Bone adapts to mechanical loads applied on it. During aging, loads decrease to a greater extent at those skeletal sites where loads increase most in earlier life. Thus, the loss of bone may occur preferentially at sites where most bone has been deposited previously; ie, bone loss could be the directional reversal of accrual. To test this hypothesis, we compared the bone mass distribution at weight-bearing (tibia) and non-weight-bearing (radius) bones among 18-year-old girls, their premenopausal mothers, and their postmenopausal maternal grandmothers. Bone and muscle properties were measured by pQCT, and polar distribution of bone mass was obtained in 55 girl-mother–maternal grandmother trio…

Differential effects of sex hormones on peri- and endocortical bone surfaces in pubertal girls.

Context: The role of sex steroids in bone growth in pubertal girls is not yet clear. Bone biomarkers are indicators of bone metabolic activity, but their value in predicting bone quality has not been studied in growing girls. Objective: This study examines the association of sex hormones and bone markers with bone geometry and density in pubertal girls. Design: The study was designed as a 2-yr longitudinal study in pubertal girls. Measurements were performed at baseline and at 1and 2-yr follow-ups. Setting: The study was conducted in a university laboratory. Participants: A total of 258 10- to 13-yr-old healthy girls at the baseline participated. Methods:Peripheralquantitativecomputedtomogr…

Mechanical jumping power in young athletes.

Mechanical jumping power was determined for 286 young male athletes representing six sports events and ranging in calendar and skeletal ages from 8.8 to 17.1 and from 7.8 to 18.1 years, respectively. The subjects performed successive maximal vertical jumps on a contact mat for 30 s. The number of jumps and their cumulative flight time after 15 and 30 s were used for calculations of mechanical power. The jumping performances of the young athletes were found to be reproducible from the age of 10-12 years in respect to the angular displacement of the knee and duration of contact. Absolute mechanical power, as well as power related to body weight, increased with calendar and skeletal ages. Of t…

Effects of aerobic exercise on home-based sleep among overweight and obese men with chronic insomnia symptoms: a randomized controlled trial

Objective: To determine the effect of a six-month aerobic exercise program on home-based sleep quality among overweight and obese men with chronic insomnia symptoms. Methods: Participants were 45 Finnish men (93% had body mass index >= 25) aged 30-65 years, with chronic months) insomnia symptoms as classified by the DSM-IV criteria. Participants were randomized into an exercise (n = 24) or control group (n = 21). The exercise group received six-month aerobic exercise intervention with one to five sessions per week of 30-60 minutes duration. The control group was instructed to maintain habitual lifestyle behaviors during the study period. Seven-night home sleep was measured with a piezoelect…

Biomechanical and skeletal muscle determinants of maximum running speed with aging.

Purpose: Aging diminishes the ability to run fast, but the specific mechanisms responsible for this deterioration remain largely unknown. In the present study, we investigated the age-related decline in sprint running ability through a cross-sectional examination of biomechanical and skeletal muscle characteristics in 77 competitive male sprinters aged 17-82 yr. Methods: Ground reaction force (GRF) and kinematic stride cycle parameters were measured during the maximum-velocity phase using a 9.4-m-long force platform. Knee extensor (KE) and ankle plantar flexor (PF) structural characteristics were investigated using ultrasonography and muscle biopsies (vastus lateralis). Force production cha…

Influence of physical activity and maturation status on bone mass and geometry in early pubertal girls1

This study aimed to evaluate the influence of leisure-time physical activity on the development of bone mass and density in early pubertal girls. Scores of physical activity were obtained from 242 Finnish girls (10-12 years old within Tanner Stages I-II) using a questionnaire. Bone mass and density were assessed using different densitometric techniques. At Tanner Stage I, active girls had significantly higher bone mineral mass (BMC) and areal bone mineral density (aBMD) of the whole body and cortical volumetric BMD and thickness of the tibial shaft compared with sedentary girls (P<0.05). On the other hand, the active girls at Tanner Stage II showed significantly higher values only in BMC an…

Serum thyroid hormones, thyrotropin and thyroxine binding globulin during prolonged strength training.

The effects of progressive strength training for 24 weeks on maximal strength and pituitary-thyroid function were studied in 21 males during the training and during the following detraining period of 12 weeks. Maximal strength increased greatly (p less than 0.001) in the first 20 weeks, followed by a plateau phase in the last 4 weeks of training. Maximal strength decreased greatly (p less than 0.001) during the detraining period. The concentrations of serum total (T4) and free thyroxine (fT4) decreased (p less than 0.05 and less than 0.01, respectively) during the training period and they rose to pretraining levels during the detraining period. During the most intense training phase (the la…

Impaired geometric properties of tibia in older women with hip fracture history.

This study evaluated side-to-side differences in tibial mineral mass and geometry in women with previous hip fracture sustained on average 3.5 years earlier. Both tibial mineral mass and geometry were found to be reduced in the fractured leg. INTRODUCTION: The purpose of this study was to evaluate side-to-side differences in tibial mineral mass and geometry after hip fracture and to assess the determinants of such differences. METHODS: Thirty-eight 60- to 85-year-old women with a previous hip fracture and 22 same-aged control women without fractures participated in the study. Bone characteristics of the distal tibia and tibial shaft of both legs were assessed using pQCT in order to compare …

Glucose polymer syrup attenuates prolonged endurance exercise-induced vasopressin release

We investigated the effect of glucose and glucose polymer ingestion on plasma arginine vasopressin (pAVP) levels, on plasma osmolality (p-osm), and on performance during two prolonged endurance events. The study subjects were 37 Finnish elite endurance athletes, of whom 18 were orienteers and 19 cross-country skiers. Plasma AVP increased in both combined glucose and glucose polymer groups, but the increase in the glucose polymer group was significantly smaller (P less than 0.001) than that in the glucose group. A significant change in p-osm caused a significant change in pAVP and vice versa. Both the orienteers and the skiers on glucose polymer tended to have more success in the competition…

Effects of resistance training on lower-extremity impairments in older people with hip fracture

Abstract Portegijs E, Kallinen M, Rantanen T, Heinonen A, Sihvonen S, Alen M, Kiviranta I, Sipila S. Effects of resistance training on lower-extremity impairments in older people with hip fracture. Objective To study the effects of resistance training on muscle strength parameters, mobility, and balance. Design Randomized controlled trial. Setting Research laboratory and senior gym. Participants Population-based sample of eligible 60- to 85-year-old community-dwelling men and women 0.5 to 7.0 years after hip fracture. Forty-six people had no contraindications and were willing to participate in the exercise trial. Intervention Twelve-week intensive progressive strength-power training (n=24),…

Metabolic response to 6-week aerobic exercise training and dieting in previously sedentary overweight and obese pre-menopausal women: A randomized trial

AbstractBackground: The aim of this study was to compare 6 weeks short-term moderate intensity aerobic exercise and dieting on serum metabolomicsand cardio-metabolic risk factors in pre-menopausal women.Methods: Ninety previously inactive overweight and obese (BMI 25e35 kg/m 2 ) women (age 41.5 7.6 years) were randomized to either a6-week Nordic walking exercise program (EX, n ¼ 45) or dietary counseling group (DI, n ¼ 45). Body composition, serum glucose, insulin andlipids were measured. Serum low-molecular-weight metabolites and lipid constituents were analyzed by nuclear magnetic resonance spec-troscopy. Measurements were done at baseline and 7 days after the last training session.Result…

Prolonged breast-feeding protects mothers from later-life obesity and related cardio-metabolic disorders

AbstractObjectiveTo investigate the long-term effects of duration of postpartum lactation on maternal body composition and risk for cardio-metabolic disorders in later life.DesignRetrospective study. Body composition was measured using dual-energy X-ray absorptiometry and serum glucose, insulin and lipids were analysed using enzymatic photometric methods 16–20 years after the last pregnancy. Medical history and lifestyle factors were collected via a self-administered questionnaire. Detailed information regarding weight change patterns during each pregnancy was obtained from personal maternity tracking records.SettingCity of Jyväskylä and surroundings in Central Finland.SubjectsTwo hundred a…

Leisure-time physical activity and high-risk fat: a longitudinal population-based twin study.

Exercise is thought to reduce high-risk body fat, but intervention studies are frequently limited by short follow-ups and observational studies by genetic selection. Therefore, we studied the effects of a physically inactive vs active lifestyle on high-risk (visceral, liver and intramuscular) fat in twin pairs discordant for leisure-time physical activity habits for over 30 years.A longitudinal population-based twin study.Sixteen middle-aged (50-74 years) same-sex twin pairs (seven monozygotic (MZ), nine dizygotic (DZ)) with long-term discordance for physical activity habits were comprehensively identified from the Finnish Twin Cohort (TWINACTIVE study). Discordance was initially defined in…

Concerted actions of insulin-like growth factor 1, testosterone, and estradiol on peripubertal bone growth: a 7-year longitudinal study.

A better understanding of how bone growth is regulated during peripuberty is important for optimizing the attainment of peak bone mass and for the prevention of osteoporosis in later life. In this report we used hierarchical models to evaluate the associations of insulin-like growth factor 1 (IGF-1), estradiol (E(2) ), and testosterone (T) with peripubertal bone growth in a 7-year longitudinal study. Two-hundred and fifty-eight healthy girls were assessed at baseline (mean age 11.2 years) and at 1, 2, 3.5, and 7 years. Serum concentrations of IGF-1, E(2) , and T were determined. Musculoskeletal properties in the left lower leg were measured using peripheral quantitative computed tomography …

Adipose Tissue Dysfunction and Altered Systemic Amino Acid Metabolism Are Associated with Non-Alcoholic Fatty Liver Disease

Article

Serum hormone concentrations during prolonged training in elite endurance-trained and strength-trained athletes.

A study of 1 year was performed on nine elite endurance-trained athletes (swimmers) and on eight elite strength-trained athletes (weightlifters) in order to examine the effects of training on the endocrine responses and on physical performance capacity. The measurements for the determination of serum hormone concentrations were performed at about 4-month intervals during the course of the year. The primary findings demonstrated that during the first and most intensive training period of the year in preparing for the primary competitions similar but statistically insignificant changes were observed in the concentrations of serum testosterone, free testosterone and cortisol in both the endura…

Psychomotor and Motor Speed in Power Athletes Self-Administering Testosterone and Anabolic Steroids

Abstract The effect of self-administered testosterone and anabolic steroids on psychomotor and motor speed were studied among five top-level power athletes. The experiment included a 26-week intensive strength training period in association with the use of exogenous hormones and a 6-week follow-up after drug withdrawal. Six athletes not using exogenous hormones served as a control group. The results indicated a similar, and in most cases insignificant, improvement (0–10%) in performance in both groups in both the simple and more complicated motor and psychomotor tests. Only in maximal vertical speed related to body weight was there more improvement in the experimental group, from 122.2 to 1…

Effect of Six-Month Diet Intervention on Sleep among Overweight and Obese Men with Chronic Insomnia Symptoms : A Randomized Controlled Trial

Growing evidence suggests that diet alteration affects sleep, but this has not yet been studied in adults with insomnia symptoms. We aimed to determine the effect of a six-month diet intervention on sleep among overweight and obese (Body mass index, BMI >= 25 kg/m(2)) men with chronic insomnia symptoms. Forty-nine men aged 30-65 years with chronic insomnia symptoms were randomized into diet (n = 28) or control (n = 21) groups. The diet group underwent a six-month individualized diet intervention with three face-to-face counseling sessions and online supervision 1-3 times per week; 300-500 kcal/day less energy intake and optimized nutrient composition were recommended. Controls were instruct…

Free amino acid pool and muscle protein balance after resistance exercise.

The aim of this study was to assess the effects of a resistance exercise session (RES) on free amino acid concentrations and protein synthesis and breakdown of the vastus lateralis (VL) muscle during recovery in male subjects.Both the exercise group (EG) and the control group (CG) consisted of six healthy physically active men. On the experiment day in fasting conditions, a stable isotopic tracer of L-[ring-2H(5)] phenylalanine was infused and EG started a heavy 50-min hypertrophic RES for lower extremities after 55 min of infusion. At the same time, CG was at rest. During recovery of 195 min after RES, several blood samples were drawn from the femoral artery (FA) and the femoral vein (FV) …

Heritability of maximal isometric muscle strength in older female twins.

The purpose of the present study was to examine genetic and environmental effects on maximal isometric handgrip, knee extension, and ankle plantar flexion strength. In addition, we wanted to investigate whether the strength of these three muscle groups shares a genetic component or whether the genetic effect is specific for each muscle group. Muscle strength was measured as part of the Finnish Twin Study on Aging in 97 monozygotic (MZ) and 102 dizygotic (DZ) female twin pairs, aged 63-76 yr. The MZ and DZ individuals did not differ from each other in age, body height, weight, or self-related health. The age-adjusted pairwise (intraclass) correlations of the MZ and DZ twins were, respective…

Acute heavy-resistance exercise–induced pain and neuromuscular fatigue in elderly women with fibromyalgia and in healthy controls: Effects of strength training

Objective To examine heavy-resistance exercise–induced acute neuromuscular fatigue, blood lactate concentration, and muscle pain in elderly women with fibromyalgia (FM) and in healthy controls before and after a period of strength training. Methods Thirteen elderly women with FM (mean ± SD age 60 ± 2 years) and 10 healthy women (mean ± SD age 64 ± 3 years) performed a heavy-resistance fatiguing protocol (5 sets of leg presses with 10 repetitions maximum) before and after a 21-week strength training period. Maximal isometric force and electromyography (EMG) activity of leg extensors and blood lactate concentration were measured during the loading. Pain was assessed by visual analog scale. Re…

Effects of heavy resistance/power training on maximal strength, muscle morphology, and hormonal response patterns in 60-75-year-old men and women.

Eleven women (TRW; 64 ± 4 yrs) and ten men (TRM; 65 ± 5 yrs) participated in the strength/power training twice a week for 24 weeks. Basal concentrations of serum total and free testosterone, growth hormone (GH), dehydroepiandrosterone sulfate (DHEAS), cortisol and sex hormone binding globulin (SHBG) as well as acute responses of serum total and free testosterone, growth hormone (GH) were measured. Maximal 1RM strength in the squat, chair rise time and muscle fibre distribution and areas of type I and IIa and IIb of the vastus lateralis were also examined. 1RM squat increased in TRW by 26 (SDIO) % (p &lt; .001), and in TRM by 35(7) % (p &lt; .001) and chair rise time improved in both groups…

Hormone replacement therapy improves contractile function and myonuclear organization of single fibres from postmenopausal monozygotic female twin pairs.

Ageing is associated with a decline in muscle mass and strength leading to increased physical dependency in old age. Postmenopausal women experience a greater decline than men of similar age in parallel with the decrease in female sex steroid hormone production. We recruited six monozygous female twin pairs (55–59 years old) where only one twin pair was on hormone replacement therapy (HRT use = 7.8 ± 4.3 years) to investigate the association of HRT with the cytoplasmic volume supported by individual myonuclei (myonuclear domain (MND) size,) together with specific force at the single fibre level. HRT use was associated with a significantly smaller (∼27%; P < 0.05) mean MND size in muscle fib…

Effects of combined strength and sprint training on regulation of muscle contraction at the whole-muscle and single-fibre levels in elite master sprinters

The aims of this study were to investigate the mechanisms underlying (1) the ageing-related motor handicap at the whole muscle, cellular, contractile protein and myonuclear levels; and (2) ageing-related differences in muscle adaptability.In vivo muscles function was studied in the knee extensors. Decreases were observed in isokinetic and isometric torque outputs in old age in the sedentary men and women and elite master sprinters. A 20-week long specific sprint and resistance training successfully improved the maximal isometric force and rate of force development in a subgroup of master sprinters.In vitro measurements were performed in muscle biopsies from the vastus lateralis muscle. Immu…

Effects of calcium, dairy product, and vitamin D supplementation on bone mass accrual and body composition in 10-12-y-old girls: a 2-y randomized trial

Little is known about the relative effectiveness of calcium supplementation from food or pills with or without vitamin D supplementation for bone mass accrual during the rapid growth period.The purpose was to examine the effects of both food-based and pill supplements of calcium and vitamin D on bone mass and body composition in girls aged 10-12 y.This placebo-controlled intervention trial randomly assigned 195 healthy girls at Tanner stage I-II, aged 10-12 y, with dietary calcium intakes900 mg/d to 1 of 4 groups: calcium (1000 mg) + vitamin D3 (200 IU), calcium (1000 mg), cheese (1000 mg calcium), and placebo. Primary outcomes were bone indexes of the hip, spine, and whole body by dual-ene…

Are skeletal muscleFNDC5gene expression and irisin release regulated by exercise and related to health?

Recently, contradictory findings have been reported concerning the function of irisin and its precursor gene, skeletal muscle FNDC5, in energy homeostasis, and the associated regulatory role of exercise and PGC-1α. We therefore evaluated whether muscle FNDC5 mRNA and serum irisin are exercise responsive and whether PGC-1α expression is associated with FNDC5 expression. The male subjects in the study performed single exercises: (1) 1 h low-intensity aerobic exercise (AE) (middle-aged, n = 17), (2) a heavy-intensity resistance exercise (RE) bout (young n = 10, older n = 11) (27 vs. 62 years), (3) long-term 21 weeks endurance exercise (EE) training alone (twice a week, middle-aged, n = 9), or …

The effects of muscle strength and power training on mobility among older hip fracture patients

The incidence of hip fractures is growing in all Western societies. The mobility of hip fracture patients does not return to the pre-fracture level even 2 years after fracture. One reason for mobility limitation may be the persistent muscle weakness on the fractured leg. The purpose of this randomized controlled study was to examine whether 12-week muscle strength and power training twice a week has an effect on mobility in 60–85-year-old hip fracture patients. Forty-three persons were randomly assigned to an intervention (n=23) and a control (n=20) group. The intervention comprised 12-week supervised intensive progressive strength–power training twice per week. All the measurers were blind…

Low volumetric BMD is linked to upper-limb fracture in pubertal girls and persists into adulthood: A seven-year cohort study

Abstract The aetiology of increased incidence of fracture during puberty is unclear. This study aimed to determine whether low volumetric bone mineral density (vBMD) in the distal radius is associated with upper-limb fractures in growing girls, and whether any such vBMD deficit persists into adulthood. Fracture history from birth to 20 years was obtained and verified by medical records in 1034 Finnish girls aged 10–13 years. Bone density and geometry at distal radius, biomarkers and lifestyle/behavioural factors were assessed in a subset of 396 girls with a 7.5-year follow-up. We found that fracture incidence peaked during puberty (relative risk 3.1 at age of 8–14 years compared to outside …

Aging and serum exomiR content in women-effects of estrogenic hormone replacement therapy.

AbstractExosomes participate in intercellular messaging by transporting bioactive lipid-, protein- and RNA-molecules and -complexes. The contents of the exosomes reflect the physiological status of an individual making exosomes promising targets for biomarker analyses. In the present study we extracted exosome microRNAs (exomiRs) from serum samples of premenopausal women (n = 8) and monozygotic postmenopausal twins (n = 10 female pairs), discordant for the use of estrogenic hormone replacement therapy (HRT), in order to see whether the age or/and the use of HRT associates with exomiR content. A total of 241 exomiRs were detected by next generation sequencing, 10 showing age, 14 HRT and 10 a…

Effects of Strength Training and Nutritional Counseling on Metabolic Health Indicators in Aging Women

Purpose: Effects of strength training (ST) and nutritional counseling (NC) on metabolic health indicators were examined in 50 aging women. Methods: Subjects performed ST for 21 weeks. NC was given to obtain sufficient energy and protein intake, and recommended intake of fat and fiber. Results: NC increased intake of protein and polyunsaturated fat by 4.5% and 10.7% and decreased intake of saturated fat by 18.3%. Serum concentrations of total cholesterol (TC), LDL-cholesterol (LDL-C), total and HDL-cholesterol (HDL-C) ratio and triacylglycerols (TAG) decreased, and serum HDL-C increased in all subjects after ST. Respectively, systolic and diastolic blood pressure and serum insulin concentrat…

Genetic determinants of heel bone properties: genome-wide association meta-analysis and replication in the GEFOS/GENOMOS consortium

Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by X-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA; n = 14 260), velocity of sound (VOS; n = 15 514) and BMD (n = 4566) in 13 discovery cohorts. Independent replication involved seven cohorts with GWA data (in silico n = 11 452) and new genotyping in 15 cohorts (de novo n = 24 902). In combined random effects, meta-analysis of the discovery and repli…

Leisure-time physical activity and nutrition: a twin study

AbstractObjectiveTo determine the association between long-term leisure-time physical activity/inactivity and eating behaviours in twin pairs discordant for physical activity for 30 years.DesignCo-twin control design with cross-sectional data collection using questionnaire on eating habits and 5 d food diary. Differences in eating behaviours between physically active and inactive co-twins were analysed with pairwise tests.SettingFinland.SubjectsSixteen same-sex twin pairs (seven monozygotic and nine dizygotic, mean age 60 years) discordant for physical activity, selected from the Finnish Twin Cohort on the basis of physical activity discordance for 30 years, blinded to their possible differ…

Neuromuscular, anaerobic, and aerobic performance characteristics of elite power athletes.

Various aspects of neuromuscular, anaerobic, and aerobic performance capacity were investigated in four powerlifters, seven bodybuilders, and three wrestlers with a history of specific training for several years. The data (means +/- SD) showed that the three subject groups possessed similar values for maximal isometric force per unit bodyweight (50.7 +/- 9.6, 49.3 +/- 4.1, and 49.3 +/- 10.9 N/kg, respectively). However, significant (P less than 0.05) differences were observed in the times for isometric force production, so that e.g., times to produce a 30% force level were shorter for the wrestlers and bodybuilders (28.3 +/- 3.1 and 26.4 +/- 6.6 ms) than that (53.3 +/- 23.7 ms) for the powe…

Electrocardiographic and other clinical correlates of walking ability in older women

Abstract The purpose of this study was to examine how resting electrocardiographic (ECG) and other clinical variables, which can be included in a routine clinical examination, predict walking ability in older women. Three hundred and twenty women (63–75 years) without overt cardiac diseases and apparent mobility limitations were studied. Measurements performed were clinical examination (standard 12-lead resting ECG, assessment of physical activity level, presence of chronic diseases, use of beta-blockers, body mass index (BMI), ability to squat, resting blood pressure) and six-minute walking test. Participants walked 533 ± 75 m in the six-minute walking test. The best electrocardiographic p…

Effects of Physical and Cognitive Training on Gait Speed and Cognition in Older Adults : A Randomized Controlled Trial

Gait speed is a measure of health and functioning. Physical and cognitive determinants of gait are amenable to interventions, but best practices remain unclear. We investigated the effects of a 12‐month physical and cognitive training (PTCT) on gait speed, dual‐task cost in gait speed, and executive functions (EFs) compared to physical training (PT) (ISRCTN52388040). Community‐dwelling older adults, who did not meet physical activity recommendations, were recruited (n=314). PT included supervised walking/balance (once weekly) and resistance/balance training (once weekly), home exercises (2‐3 times weekly) and moderate aerobic activity 150 minutes/week in bouts of >10 minutes. PTCT included …

Heavy resistance exercise training and skeletal muscle androgen receptor expression in younger and older men

Effects of heavy resistance exercise on serum testosterone and skeletal muscle androgen receptor (AR) concentrations were examined before and after a 21-week resistance training period. Seven healthy untrained young adult men (YT) and ten controls (YC) as well as ten older men (OT) and eight controls (OC) volunteered as subjects. Heavy resistance exercise bouts (5 × 10 RM leg presses) were performed before and after the training period. Muscle biopsies were obtained before and 1h and 48 h after the resistance exercise bouts from m.vastus lateralis (VL) to determine cross-sectional area of muscle fibers (fCSA) and AR mRNA expression and protein concentrations. No changes were observed in YC …

Effects of a 20-week high-intensity strength and sprint training program on tibial bone structure and strength in middle-aged and older male sprint athletes: a randomized controlled trial.

This randomized, controlled, high-intensity strength and sprint training trial in middle-aged and older male sprint athletes showed significant improvements in mid-tibial structure and strength. The study reveals the adaptability of aging bone, suggesting that through a novel, intensive training stimulus it is possible to strengthen bones during aging. High-load, high-speed and impact-type exercise may be an efficient way of improving bone strength even in old age. We evaluated the effects of combined strength and sprint training on indices of bone health in competitive masters athletes, who serve as a group of older people who are likely to be able to participate in vigorous exercise of th…

What Makes a 97-Year-Old Man Cycle 5,000 km a Year?

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; The nature versus nurture debate is one of the oldest issues in the study of longevity, health and successful aging. &lt;b&gt;&lt;i&gt;Objective:&lt;/i&gt;&lt;/b&gt; We present a 97-year-old man (I.K.) as an example of the effects of habitual exercise on the aging process. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Extensive assessments included medical examinations, interviews, musculoskeletal structure, performance characteristics, cognitive function and gut microbiota composition. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; I.K. suffers from iatrogenic hypogonadism, prostate cancer, hypothyroidism and a history of deep popliteal th…

Normal-weight obesity and cardiometabolic risk : A 7-year longitudinal study in girls from prepuberty to early adulthood

Objective: To study whether normal-weight obesity in childhood is associated with increased cardiometabolic risk in early adulthood. Methods: This study assessed data for 236 girls followed from prepuberty to early adulthood. Growth chart data were obtained from birth to 18 years. Body composition was assessed by dual-energy x-ray absorptiometry and cardiometabolic risk by calculating continuous clustered risk score (at ages 11, 14, and 18). The association of body weight status with cardiometabolic risk from childhood to early adulthood was examined. Results: Subjects with normal-weight obesity were virtually indistinguishable from their normal-weight lean peers in terms of relative body w…

Relationship of sex hormones to bone geometric properties and mineral density in early pubertal girls.

This study aimed to evaluate the associations among serum 17beta-estradiol (E2), testosterone (T), sex hormone-binding globulin (SHBG), bone geometric properties, and mineral density in 248 healthy girls between the ages of 10 and 13 yr old. The left tibial shaft was measured by peripheral quantitative computed tomography (Stratec XCT-2000; Stratec Medizintechnik, GmbH, Pforzheim, Germany). The cortical bone and marrow cavity areas were expressed as proportions of the total tibial cross-sectional area (CSA). Cortical thickness and total volumetric bone mineral density (vBMD) were also determined. These tibial geometric and densitometric measures were correlated against the serum sex hormone…

Effects of Strength Training and Reduced Training on Functional Performance and Metabolic Health Indicators in Middle-Aged Men

Changes in muscular fitness and metabolic health indicators were examined in 22 men (57.9 +/- 6.6 years, BMI 24.5 +/- 2.6 kg/m (2)) and 21 control men (58.2 +/- 6.1 years, BMI 25.4 +/- 2.8 kg/m (2)) during two consecutive 21-week periods: 1) whole body progressive strength training (ST: twice a week), and 2) continued reduced training (CRT: 3 ST sessions/2 weeks, n = 17 + 17). After the 21-week ST period, maximal strength of leg extensors increased in the ST group by 19.6 +/- 7.6 % vs. 2.8 +/- 4.4 % (p < 0.001) and also 10-m walking time and 10-step stair-climbing time shortened by - 17.2 +/- 7.6 % vs. 4.1 +/- 3.9 % (p < 0.01) and by - 8.2 +/- 6.8 % vs. - 3.0 +/- 6.8 % (p < 0.05) compared t…

Effects of intensive strength-power training on sense of coherence among 60-85-year-old people with hip fracture: A randomized controlled trial

Background and aims: Older people with disabilities are at increased risk of psychological health decline. There are no earlier studies on the effects of resistance training on sense of coherence (SOC) among older people with a history of hip fracture. The aim of this study is to test the effects of intensive 12-week strength-power training on SOC among older adults after hip fracture. Methods: A clinical sample of 60-85-year-old community-dwelling men and women was studied, 0.5. to 7.0 years after hip fracture. Forty-six had no contraindications for participation and were randomized into training (n=24) and control groups (n=22). The training group participated in a 12-week, individually t…

Anabolic-Androgenic Steroid Effects on Endocrinology and Lipid Metabolism in Athletes

As exhaustive reviews concerning hormonal alteration (Bunt 1986) and lipid metabolism (Goldberg & Elliot 1987; Hurley & Kokkinos 1987) during normal physical exercise and training have recently been published in the Journal, this article is designed to focus only on the biological actions of synthetic anabolic-androgenic steroids on endocrinology and lipid metabolism and the interactions between both of these during training in adult male athletes.

Effects of Concurrent Strength and Endurance Training on Physical Fitness and Symptoms in Postmenopausal Women With Fibromyalgia: A Randomized Controlled Trial

Abstract Valkeinen H, Alen M, Hakkinen A, Hannonen P, Kukkonen-Harjula K, Hakkinen K. Effects of concurrent strength and endurance training on physical fitness and symptoms in postmenopausal women with fibromyalgia: a randomized controlled trial. Objective To examine the effectiveness of concurrent strength and endurance training on muscle strength, aerobic and functional performance, and symptoms in postmenopausal women with fibromyalgia (FM). Design Randomized controlled trial. Setting Local gym and university research laboratory. Participants Twenty-six women with FM. Intervention Progressive and supervised 21-week concurrent strength and endurance training. Main Outcome Measures Muscle …

Effects of Strength Training on Muscle Strength Characteristics, Functional Capabilities, and Balance in Middle-Aged and Older Women

Progressive strength training can lead to substantial increases in maximal strength and mass of trained muscles, even in older women and men, but little information is available about the effects of strength training on functional capabilities and balance. Thus, the effects of 21 weeks of heavy resistance training--including lower loads performed with high movement velocities--twice a week on isometric maximal force (ISOmax) and force-time curve (force produced in 500 milliseconds, F0-500) and dynamic 1 repetition maximum (1RM) strength of the leg extensors, 10-m walking time (10WALK) and dynamic balance test (DYN.D) were investigated in 26 middle-aged (MI; 52.8 +/- 2.4 years) and 22 older …

Randomoitu kontrolloitu tutkimus keski-ikäisten miesten unettomuudesta

Unettomuus on yleinen ongelma, jonka hoito on kansaterveydellisesti erittäin tärkeää. Koska unettomuuden yleisimmällä hoitokeinolla lääkityksellä on paljon haitallisia sivuvaikutuksia, on tärkeää tutkia unettomuuden vaihtoehtoisia hoitokeinoja. Tämän Pro Gradu -tutkielman tarkoituksena on selvittää kestävyysliikunnan vaikutusta unen laatuun ja määrään keski-ikäisillä unettomuudesta kärsivillä miehillä. Satunnaistetussa kontrolloidussa tutkimuksessa 42 vähän liikkuvaa vapaaehtoista 30–65-vuotiasta unettomuudesta kärsivää miestä Keski-Suomen sairaanhoitopiiristä (keski-ikä 51 [1.6] vuotta) jaettiin liikunta- ja kontrolliryhmään. Liikuntaryhmäläiset noudattivat yksilölli-sesti suunniteltua pro…

Aging, muscle fiber type, and contractile function in sprint-trained athletes

Biopsy samples were taken from the vastus lateralis of 18- to 84-yr-old male sprinters ( n = 91). Fiber-type distribution, cross-sectional area, and myosin heavy chain (MHC) isoform content were identified using ATPase histochemistry and SDS-PAGE. Specific tension and maximum shortening velocity ( Vo) were determined in 144 single skinned fibers from younger (18–33 yr, n = 8) and older (53–77 yr, n = 9) runners. Force-time characteristics of the knee extensors were determined by using isometric contraction. The cross-sectional area of type I fibers was unchanged with age, whereas that of type II fibers was reduced ( P &lt; 0.001). With age there was an increased MHC I ( P &lt; 0.01) and re…

Combination of hormone replacement therapy and high physical activity is associated with differences in Achilles tendon size in monozygotic female twin pairs.

Estrogen concentration has been suggested to play a role in tendon abnormalities and injury. In physically active postmenopausal women, hormone replacement therapy (HRT) has been suggested to decrease tendon diameter. We hypothesized that HRT use and physical activity are associated with Achilles tendon size and tissue structure. The study applied cotwin analysis of fourteen 54- to 62-yr-old identical female twin pairs with current discordance for HRT use for an average of 7 yr. Achilles tendon thickness and cross-sectional areas were determined by ultrasonography, and tendon structural organization was analyzed from the images using linear discriminant analysis (LDA). Maximal voluntary and…

Basal concentrations and acute responses of serum hormones andstrength development during heavy resistance training in middle-aged andelderly men and women

Effects of 6 months of heavy resistance training combined with explosive exercises on both basal concentrations and acute responses of total and free testosterone, growth hormone (GH), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), cortisol and sex hormone-binding globulin (SHBG), as well as voluntary neural activation and maximal strength of knee extensors were examined in 10 middle-aged men (M40; 42 +/- 2 years), 11 middle-aged women (W40; 39 +/- 3 years), 11 elderly men (M70; 72 +/- 3 years), and in 10 elderly women (W70; 67 +/- 3 years). The maximal integrated electromyographic (iEMG) and 1 repetition maximum (RM) knee-extension values remained unaltered in all g…

Familial resemblance and diversity in bone mass and strength in the population are established during the first year of postnatal life

Familial resemblance and diversity in bone structure and strength in adulthood are determined in part during growth. Whether these characteristics are established during gestation or shortly after birth is not known. Total-body, lumbar spine, and femoral neck size and mass and indices of tibial bending strength and distal radial compressive strength were measured using bone densitometry and quantitative computed tomography in 236 girls at 18.5 years of age. Among them, 219, 141, and 105 girls had crown-heel length (CHL) and weight recorded at birth and at 6 and 12 months of age, and then height and weight were recorded at 3, 5, 10, 13, and 15 years of age in 181, 176, 127, 111, and 228 girl…

Short vs. Long Rest Period Between the Sets in Hypertrophic Resistance Training: Influence on Muscle Strength, Size, and Hormonal Adaptations in Trained Men

Acute and long-term hormonal and neuromuscular adaptations to hypertrophic strength training were studied in 13 recreationally strength-trained men. The experimental design comprised a 6-month hypertrophic strength-training period including 2 separate 3-month training periods with the crossover design, a training protocol of short rest (SR, 2 minutes) as compared with long rest (LR, 5 minutes) between the sets. Basal hormonal concentrations of serum total testosterone (T), free testosterone (FT), and cortisol (C), maximal isometric strength of the leg extensors, right leg 1 repetition maximum (1RM), dietary analysis, and muscle cross-sectional area (CSA) of the quadriceps femoris by magneti…

Neuromuscular adaptation during prolonged strength training, detraining and re-strength-training in middle-aged and elderly people.

Effects of a 24-week strength training performed twice weekly (24 ST) (combined with explosive exercises) followed by either a 3-week detraining (3 DT) and a 21-week re-strength-training (21 RST) (experiment A) or by a 24-week detraining (24 DT) (experiment B) on neural activation of the agonist and antagonist leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris, maximal isometric and one repetition maximum (1-RM) strength and jumping (J) and walking (W) performances were examined. A group of middle-aged (M, 37–44 years, n=12) and elderly (E, 62–77, n=10) and another group of M (35–45, n=7) and E (63–78, n=7) served as subjects. In experiment A, the 1-RM increased subs…

Changes in agonist-antagonist EMG, muscle CSA, and force during strength training in middle-aged and older people

Effects of 6 mo of heavy-resistance training combined with explosive exercises on neural activation of the agonist and antagonist leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris, as well as maximal and explosive strength were examined in 10 middle-aged men (M40; 42 ± 2 yr), 11 middle-aged women (W40; 39 ± 3 yr), 11 elderly men (M70; 72 ± 3 yr) and 10 elderly women (W70; 67 ± 3 yr). Maximal and explosive strength remained unaltered during a 1-mo control period with no strength training. After the 6 mo of training, maximal isometric and dynamic leg-extension strength increased by 36 ± 4 and 22 ± 2% ( P &lt; 0.001) in M40, by 36 ± 3 and 21 ± 3% ( P &lt; 0.001) in M7…

Effect of explosive type strength training on isometric force- and relaxation-time, electromyographic and muscle fibre characteristics of leg extensor muscles.

Eleven male subjects (20-32 years) accustomed to strength training went through progressive, high-load strength training for 24 weeks with intensities ranging variably between 70 and 120% during each month. This training was also followed by a 12-week detraining period. An increase of 26.8% (P less than 0.001) in maximal isometric strength took place during the training. The increase in strength correlated (P less than 0.05) with significant (P less than 0.05-0.01) increases in the neural activation (IEMG) of the leg extensor muscles during the most intensive training months. During the lower-intensity training, maximum IEMG decreased (P less than 0.05). Enlargements of muscle-fibre areas, …

Accelerometer-measured and self-reported physical activity in relation to extraversion and neuroticism: a cross-sectional analysis of two studies

Background Personality reflects relatively stable and pervasive tendencies in feeling, thinking and behaving. While previous studies have found higher extraversion and lower neuroticism to be linked to higher self-reported physical activity levels, larger studies using accelerometer-measured physical activity are lacking. This study investigated the cross-sectional associations of extraversion and neuroticism with both accelerometer-measured and self-reported physical activity and the role of these personality traits in possible discrepancies between these two measures of physical activity among Finnish adults. Methods Two community-dwelling samples were used in this study: a) 47–55-yr-old …

Global gene expression profiles in skeletal muscle of monozygotic female twins discordant for hormone replacement therapy

Summary Aging is accompanied by inexorable loss of muscle tissue. One of the underlying causes for this is the massive change in the hormonal milieu of the body. The role of a female sex steroid – estrogen – in these processes is frequently neglected, although the rapid decline in its production coincides with a steep deterioration in muscle performance. We recruited 54- to 62-year-old monozygotic female twin pairs discordant for postmenopausal hormone replacement therapy (HRT, n = 11 pairs; HRT use 7.3 ± 3.7 years) from the Finnish Twin Cohort to investigate the association of long-term, estrogen-based HRT with skeletal muscle transcriptome. Pathway analysis of muscle transcript profiles r…

Does Systemic Low-Grade Inflammation Associate With Fat Accumulation and Distribution? A 7-Year Follow-Up Study With Peripubertal Girls

Knowledge about the interrelationship between adiposity and systemic low-grade inflammation during pubertal growth is important in detecting early signs of obesity-related metabolic disorders.The objective of the study was to evaluate the developmental trajectories of fat mass (FM) and high sensitive C-reactive protein (hsCRP) levels and factors that could explain the relationship between FM and hsCRP in girls from prepuberty to early adulthood.This was a 7.5-year longitudinal study.The study was conducted at the University of Jyväskylä Sports and Health Science laboratory.Three hundred ninety-six healthy Finnish girls aged 11.2 ± 0.8 years participated in the study.Body composition was ass…

Effects of prolonged and maintenance strength training on force production, walking, and balance in aging women and men

To examine effects of 21-week twice/week strength training (ST) period followed by an additional 21-week twice or once/week ST period on force production, walking and balance in aging people. Seventy-two women (58 ± 7 years; W) and 63 (58 ± 6 years) men (M) were randomized for the first 21-week ST period: STW and STM, control (C) CW and CM. Training participants were randomized for the second 21-week ST period: once/week STWx1 and STMx1, twice/week STWx2 and STMx2. LegPress, isometric leg extension rate of force development (RFD), walking time, and balance. First 21-week ST period: leg press, RFD, balance, and walking improved significantly in STW and STM. Second 21-week ST period: leg pres…

Genetic influences on resting electrocardiographic variables in older women: a twin study.

Background: Previous studies in young and middle-aged men and women have shown that resting electrocardiographic (ECG) variables are influenced by genetic factors. However, the extent to which resting ECG variables are influenced by genetic factors in older women is unknown. Thus, the aim of this study was to estimate the relative contribution of genetic and environmental influences to individual differences in resting ECG variables among older female twins without overt cardiac diseases. Methods: Resting ECG recordings were obtained from 186 monozygotic and 203 dizygotic twin individuals, aged 63–76 years. Quantitative genetic modeling was used to decompose the phenotypic variance in each …

Association Between Exercise and Pubertal BMD Is Modulated by Estrogen Receptor α Genotype

Genetic and environmental factors contribute to bone mass, but the ways they interact remain poorly understood. This study of 245 pre- and early pubertal girls found that the PvuII polymorphism in the ER- gene modulates the effect of exercise on BMD at loaded bone sites. Introduction: Impaired achievement of bone mass at puberty is an important risk factor for the development of osteoporosis in later life. Genetic, as well as environmental, factors contribute to bone mass, but the ways they interact with each other remain poorly understood. Materials and Methods: We investigated the interaction between a PvuII polymorphism at the ER- gene and physical activity (PA) on the modulation of bone…

Neuromuscular and hormonal responses in elite athletes to two successive strength training sessions in one day

Acute neuromuscular and endocrine adaptations to weight-lifting were investigated during two successive high intensity training sessions in the same day. Both the morning (I) (from 9.00 to 11.00 hours) and the afternoon (II) (from 15.00 hours to 17.00 hours) training sessions resulted in decreases in maximal isometric strength (p less than 0.01 and less than 0.05), shifts (worsening) in the force-time curve in the absolute scale (p less than 0.05 and ns.) and in decreases in the maximal integrated EMG (p less than 0.01 and less than 0.05) of the selected leg extensor muscles. Increases in serum total (p less than 0.05) and free testosterone (p less than 0.01) and in cortisol (p less than 0.…

Physical Fitness in Postmenopausal Women with Fibromyalgia

The purpose of this study was to compare physical fitness and health-related quality-of-life between twenty-three postmenopausal women with fibromyalgia (age 58 +/- 3 years) and eleven healthy women (58 +/- 5 years). Aerobic fitness and isometric force of different muscle groups were measured. Functional performance was assessed by walking and stair-climbing times. Symptoms were assessed by visual analog scale and quality-of-life by RAND-36 questionnaire. Women with fibromyalgia had significantly lower isometric force in bilateral leg extensors (1285 vs. 1898 N), unilateral knee extensors (414 vs. 502 N) and flexors (197 vs. 235 N) than healthy women, but no differences were observed in for…

Long Term Leisure Time Physical Activity Has a Positive Effect on Bone Mass Gain in Girls

The purpose of this 7-year prospective longitudinal study was to examine whether the level and consistency of leisure-time physical activity (LTPA) during adolescence affected the bone mineral content (BMC) and bone mineral density (BMD) attained at early adulthood. The study subjects were 202 Finnish girls who were 10 to 13 years of age at baseline. Bone area (BA), BMC, and BMD of the total body (TB), total femur (TF), and lumbar spine (L2–L4) were assessed by dual-energy X-ray absorptiometry (DXA). Scores of LTPA were obtained by questionnaire. Girls were divided into four groups: consistently low physical activity (GLL), consistently high (GHH), and changed from low to high (GLH) and fro…

Effect of long-term leisure time physical activity on lean mass and fat mass in girls during adolescence.

The purpose of this 7-yr prospective longitudinal study was to examine if the level and consistency of leisure-time physical activity (LTPA) during adolescence affected the quantity and distribution of lean mass (LM) and fat mass (FM) at early adulthood. The study subjects were 202 Finnish girls who were 10–13 yr old at baseline. LM and FM of the total body (TB), arms, legs, and trunk were assessed by dual-energy X-ray absorptiometry. Muscle cross-sectional area (mCSA) of the left leg was assessed by peripheral quantitative computed tomography. Scores of LTPA were obtained by questionnaire. Girls were divided into four groups comprising those with consistently low (GLL) or consistently hig…

Changes in neuromuscular performance and muscle fiber characteristics of elite power athletes self-administering androgenic and anabolic steroids

The influence of androgenic-anabolic steroid-induced changes in measures of body composition, muscle fiber characteristics and various aspects of the neuromuscular performance of the leg extensor muscles was investigated in five experimental and six control power athletes during the 24-week programmed strength training followed by the additional six week training without hormone drugs. The mean values of the dosages of self-administration during the 24-week period were 31.0 +/- 14.3 mg/day for anabolic steroids (methandienone, stanozolol, nandrolone) and 178.4 +/- 82.7 mg/week for testosterone. During the 24-week hormone period the experimental group gained in fat-free weight (p less than 0…

Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture

Bone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top BMD-associated markers for replication in 50,933 independent subjects and for association with risk of low-trauma fracture in 31,016 individuals with a history of fracture (cases) and 102,444 controls. We identified 56 loci (32 new) associated with BMD at genome-wide significance (P &lt; 5 × 10 -8). Several of these factors cluster within the RANK-RANKL-OPG, mesenchymal stem cell differentiation, endochondral…

Growth and aging of proximal femoral bone - a study with women spanning three generations

Abstract. Osteoporotic hip fracture is a serious clinical event associated with high morbidity and mortality. Understanding femoral growth patterns is important for promoting bone health in the young and preventing fractures in later life. In this study, growth patterns of areal bone mineral density (aBMD) and geometric properties of the proximal femur were measured by dual-energy X-ray absorptiometry (GE Lunar Prodigy, USA). They were studied in 251 girls from premenarche (11.2±0.7 yrs) to late adolescence (18.3±1.1 yrs), and compared to their premenopausal mothers (n=128, aged 44.9±4.1 yrs) and postmenopausal grandmothers (n=128, aged 70.0±6.3 yrs). Hip axis length (HAL) was the first to …

Does sex hormone-binding globulin cause insulin resistance during pubertal growth?

Background The directional influences between serum sex hormone-binding globulin (SHBG), adiposity and insulin resistance during pubertal growth remain unclear. The aim of this study was to investigate bidirectional associations between SHBG and insulin resistance (HOMA-IR) and adiposity from childhood to early adulthood. Methods Participants were 396 healthy girls measured at baseline (age 11.2 years) and at 1, 2, 4 and 7.5 years. Serum concentrations of estradiol, testosterone and SHBG were determined by ELISA, glucose and insulin by enzymatic photometry, insulin-like growth factor 1 (IGF-1) by time-resolved fluoroimmunoassays, whole-body fat mass by dual-energy X-ray absorptiometry and …

Changes in electromyographic activity, muscle fibre and force production characteristics during heavy resistance/power strength training in middle-aged and older men and women

The effects of a 6-month resistance training (2 day/week) designed to develop both strength and power on neural activation by electromyographic activity (EMG) of the agonist and antagonist knee extensors, muscle fibre proportion and areas of type I, IIa, and IIb of the vastus lateralis (VL) as well as maximal concentric one repetition maximum (1 RM) strength and maximal and explosive isometric strength of the knee extensors were examined. A total of 10 middle-aged men (M40; 42 +/- 2), 11 middle-aged women (W40; 39 +/- 3), 11 elderly men (M70; 72 +/- 3) and 10 elderly women (W70; 67 +/- 3) served as subjects. Maximal and explosive strength values remained unaltered during a 1-month control p…

Serum metabolic profiles in overweight and obese women with and without metabolic syndrome.

Objective: To identify serum biomarkers through metabolomics approach that distinguishes physically inactive overweight/obese women with metabolic syndrome from those who are metabolically healthy, independent of body weight and fat mass. Methods: We applied nuclear magnetic resonance spectroscopy-based profiling of fasting serum samples to examine the metabolic differences between 78 previously physically inactive, body weight and fat mass matched overweight/obese premenopausal women with and without MetS. MetS was defined as the presence of at least three of the following five criteria: waist circumference ≥ 88 cm, serum triacylglycerol ≥ 1.7 mmol/L, and high density lipoprotein cholester…

Influence of long-term postmenopausal hormone-replacement therapy on estimated structural bone strength: A study in discordant monozygotic twins

Although postmenopausal hormone-replacement therapy (HRT) is known to prevent fractures, knowledge on the influence of long-term HRT on bone strength and its determinants other than areal bone mineral density is scarce. This study used a genetically controlled design with 24 monozygotic female twin pairs aged 54 to 72 years in which one cotwin was using HRT (mean duration 8 years) and the other had never used HRT. Estimated bone strength, cross-sectional area, volumetric bone mineral density, bone mineral mass, and cross-sectional density and mass distributions were assessed in the tibial shaft, distal tibia, and distal radius with peripheral computed tomography (pQCT). In the tibial shaft,…

Comparison of heart rate monitoring with indirect calorimetry for energy expenditure evaluation

Abstract Purpose The purpose of this study was to compare established methods with newly-developed methods for estimating the total energy expenditure (TEE). Methods The study subjects comprised 46 individuals, including 16 middle-aged men (mean age 51.4 years), 14 middle-aged women (mean age 49.9 years) and 16 young women (mean age 19.1 years). The TEE was estimated from 24-h heart rate (HR) data using newly-developed software (MoveSense HRAnalyzer 2011a, RC1, Suunto Oy, Vantaa, Finland), and was compared against the TEE determined using doubly labeled water (DLW). Agreement between the two methods was analyzed using Bland and Altman plots. Results The HR method yielded similar TEE values …

Associations of disordered sleep with body fat distribution, physical activity and diet among overweight middle-aged men

This cross-sectional study aimed to investigate whether body fat distribution, physical activity levels and dietary intakes are associated with insomnia and/or obstructive sleep apnea among overweight middle-aged men. Participants were 211 Finnish men aged 30-65 years. Among the 163 overweight or obese participants, 40 had insomnia only, 23 had obstructive sleep apnea only, 24 had comorbid insomnia and obstructive sleep apnea and 76 were without sleep disorder. The remaining 48 participants had normal weight without sleep disorder. Fat mass, levels of physical activity and diet were assessed by dual-energy X-ray densitometry, physical activity questionnaire and 3-day food diary, respectivel…

The associations of serum serotonin with bone traits are age- and gender-specific

Context Serotonin plays a potential role in bone metabolism, but the nature and extent of this relationship is unclear and human studies directly addressing the skeletal effect of circulating serotonin are rare. Objective The study aimed to investigate the associations between serum serotonin and bone traits at multiple skeletal sites in women and men. Subjects and Methods Subjects were part of the CALEX-family study and comprised 235 young women, 121 premenopausal women, 124 postmenopausal women, and 168 men. Body composition was assessed using DXA, as was areal bone mineral density (aBMD) of spine, femur and whole body. In addition, pQCT was used to determine bone properties at tibial mid…

Androgenic-anabolic steroid effects on serum thyroid, pituitary and steroid hormones in athletes.

Endocrine responses in seven power athletes were investigated during a 12 week strength training period, when the athletes were taking high doses of androgenic-anabolic steroids, and during the 13 weeks following drug withdrawal. During the use of steroids significant decreases (P less than 0.05 to 0.001) in the serum concentrations of thyroid stimulating hormone, thyroxine, triidothyronine, free thyroxine, and thyroid hormone-binding globulin (TBG) were found, whereas the value of triidothyronine uptake increased (P less than 0.001). In relation to the changes in the thyroid function parameters measured, we suggest that the primary target of androgen action was TBG biosynthesis. In five of…

Effects of combined endurance and strength training on muscle strength, power and hypertrophy in 40-67-year-old men

Both strength and endurance training have several positive effects on aging muscle and physical performance of middle-aged and older adults, but their combination may compromise optimal adaptation. This study examined the possible interference of combined strength and endurance training on neuromuscular performance and skeletal muscle hypertrophy in previously untrained 40-67-year-old men. Maximal strength and muscle activation in the upper and lower extremities, maximal concentric power, aerobic capacity and muscle fiber size and distribution in the vastus lateralis muscle were measured before and after a 21-week training period. Ninety-six men [mean age 56 (SD 7) years] completed high-int…

Effects of progressive resistance training on physical disability among older community-dwelling people with history of hip fracture

Background and aims: Hip fracture is a common trauma in older people, and often leads to decreased muscle strength and increased physical disability. This randomized controlled trial examined whether three months of progressive resistance training (PRT) can reduce physical disability among older people with a history of hip fracture. Methods: A population-based sample of 60-85-year-old community-dwelling persons, with hip fractures sustained on average three years earlier, were enrolled in the study. Of 78 people participating in laboratory assessments, those without contraindications for participation in resistance training were randomly assigned to a training group (TG, n=22) or a control…

Cannabinoid receptor 1 and acute resistance exercise – In vivo and in vitro studies in human skeletal muscle

Abstract Aim This study aimed to determine whether Cannabinoid receptor 1 (CB1) is involved in mammalian target of rapamycin (mTOR) signaling and skeletal muscle protein synthesis. Methods This study used human vastus lateralis skeletal muscle biopsies obtained before and after a resistance exercise (RE) bout in young men (n = 18). The signaling mechanisms were studied in vitro in human myotubes. Protein expression was determined by Western blot and confocal microscopy, and gene expression by quantitative PCR. Protein synthesis was measured in vitro using puromycin-based SuNSET technique. Results In human skeletal muscle, an anabolic stimulus in the form of RE down-regulated CB1 expression.…

Physical inactivity and pain in older men and women with hip fracture history

Hip fracture patients often suffer from pain for several months after surgery. This may lead to physical inactivity and subsequent mobility limitation and disability. The purpose of this study was to investigate the association between severe musculoskeletal pain and the level of physical activity in older people with a history of hip fracture. Data were collected from 60- to 85-year-old (n = 78) community-dwelling people, 0.7–7.5 years after hip fracture. Physical activity was assessed with the Yale Physical Activity Survey (YPAS). According to the YPAS summary index distribution, the participants were divided into the physically inactive and physically active groups. Musculoskeletal pain …

Balance Confidence Was Associated With Mobility and Balance Performance in Older People With Fall-Related Hip Fracture: A Cross-Sectional Study

Abstract Portegijs E, Edgren J, Salpakoski A, Kallinen M, Rantanen T, Alen M, Kiviranta I, Sihvonen S, Sipila S. Balance confidence was associated with mobility and balance performance in older people with fall-related hip fracture: a cross-sectional study. Objective To study the relationship between balance confidence, a concept closely related to fear of falling, mobility and balance performance, and perceived mobility limitation in older people after a fall-related hip fracture. Design Cross-sectional analyses of pretrial data of 2 randomized controlled trials of physical rehabilitation. Setting University research center. Participants Community-dwelling people aged over 60 years, 6 week…

Interexaminer reliability of low back pain assessment using the McKenzie method.

STUDY DESIGN A test-retest design was used. OBJECTIVE To assess interexaminer reliability of the McKenzie method for performing clinical tests and classifying patients with low back pain. SUMMARY OF BACKGROUND DATA Clinical methods and tests classifying patients with nonspecific low back pain have been based mainly on symptom duration or extent of pain referral. The McKenzie mechanical diagnostic and classification approach is a widely used noninvasive, low-technology method of assessing patients with low back pain. However, little is known about the interexaminer reliability of the method, previous studies having yielded conflicting results. METHODS For this study, 39 volunteers with low b…

Relation of PvuII site polymorphism in the COL1A2 gene to the risk of fractures in prepubertal Finnish girls.

Genetic susceptibility to fractures may be detectable in early childhood. We evaluated the associations between the polymorphic PvuII site of the COL1A2 gene and bone properties assessed by different modalities (dual-energy X-ray absorptiometry; peripheral quantitative computed tomography; gel coupling scanning quantitative ultrasonometry; ultrasound bone sonometry), bone turnover markers, and the occurrence of fractures in 244 prepubertal Finnish girls. Tanner stage and physical characteristics did not differ significantly among girls with different COL1A2 genotypes. The polymorphism was not significantly associated with different bone properties or any of the bone turnover markers when gi…

Associations of neuroticism with falls in older adults : do psychological factors mediate the association?

OBJECTIVES Neuroticism predicts falls in older people. In addition, concern about falling and depressive symptoms are associated with fall risk. This study examined whether concern about falling and depressive symptoms mediate the association between neuroticism and falls. METHOD Cross-sectional data on 314 community-dwelling people aged 70–85 years were utilized. Neuroticism was assessed with a short modified form of the Eysenck Personality Inventory. Indoor and outdoor falls during the past year were self-reported. Concern about falling was assessed with the Falls Efficacy Scale-International and depressive symptoms with the Geriatric Depression Scale-15. Path modeling was used to examine…

Leg extension power asymmetry and mobility limitation in healthy older women

Objective To investigate the association of asymmetry in leg extension power (LEP) with walking and standing balance. Design Cross-sectional analysis. Setting Research laboratory. Participants Healthy female twins (N=419), ages 63 to 75 years. Interventions Not applicable. Main Outcome Measures The LEP difference between the stronger and the weaker leg, measured with the Nottingham power rig, was calculated. Ten-meter maximal walking velocity was assessed in a laboratory corridor on a wide (170cm) and narrow (35cm) track, and the ability to maintain tandem stance for 20 seconds was recorded. Results The mean LEP difference ± standard deviation between the legs was 15%±9% (P<.001). Those wit…

Motives for and Barriers to Physical Activity in Twin Pairs Discordant for Leisure Time Physical Activity for 30 Years

Long-term persistent physical activity is important in the prevention of chronic diseases, but a large number of people do not participate in physical activity to obtain health benefits. The purpose of this study was to examine the motives and perceived barriers to long-term engagement in leisure time physical activity. Same-sex twin pairs (N=16, mean age 60) discordant for physical activity over 30 years were identified from the Finnish Twin Cohort. We evaluated participants' physical activity motivation with the 73-item Recreational Exercise Motivation Measure and assessed barriers to physical activity with a 25-item questionnaire. The characteristics of physical activity motivation and p…

Muscle function in monozygotic female twin pairs discordant for hormone replacement therapy

Introduction: Postmenopausal monozygotic twin pairs discordant for hormone replacement therapy (HRT) provide an advantageous study design controlling for genetic background for elucidating the relationships between aging, sex hormone levels, muscle strength, contractile capacity, and fatigability. Methods: Thirteen postmenopausal monozygotic twin pairs discordant for HRT were measured for maximal voluntary torque (MVC) and twitch characteristics using electrical stimulation before and after intermittent dynamic plantarflexor exercise until exhaustion. Results: Peak twitch torque was 32% higher in HRT users than in their non-HRT, genetically identical sisters (P = 0.002), but MVC did not dif…

Leisure-time physical activity and artery lumen diameters: A monozygotic co-twin control study

Exercise is thought to increase the diameter of the conduit arteries supplying the muscles involved. We studied the effects of a physically active vs inactive lifestyle on artery diameters in monozygotic (MZ) twin pairs discordant over 30 years for leisure-time physical activity habits. In a population-based co-twin control study design, six middle-aged (50-65 years) same-sex MZ twin pairs with long-term discordance for physical activity were comprehensively identified from the Finnish Twin Cohort (TWINACTIVE study). Discordance was initially defined in 1975 and the same co-twin remained significantly more active during the 32-year follow-up. The main outcomes were arterial lumen diameters …

Strength training induced adaptations in neuromuscular function of premenopausal women with fibromyalgia: comparison with healthy women.

Objective—To investigate the eVects of 21 weeks’ progressive strength training on neuromuscular function and subjectively perceived symptoms in premenopausal women with fibromyalgia (FM). Methods—Twenty one women with FM were randomly assigned to experimental (FMT) or control (FMC) groups. Twelve healthy women served as training controls (HT). The FMT and HT groups carried out progressive strength training twice a week for 21 weeks. The major outcome measures were muscle strength and electromyographic (EMG) recordings. Secondary outcome measures were pain, sleep, fatigue, physical function capacity (Stanford Health Assessment Questionnaire), and mood (short version of Beck’s depression inde…

Bone and Muscle Development During Puberty in Girls: A Seven-Year Longitudinal Study

The growth of lean mass precedes that of bone mass, suggesting that muscle plays an important role in the growth of bone. However, to date, no study has directly followed the growth of bone and muscle size through puberty and into adulthood. This study aimed to test the hypothesis that the growth of muscle size precedes that of bone size (width and length) and mass during puberty. Bone and muscle properties were measured using pQCT and DXA in 258 healthy girls at baseline (mean age, 11.2 yr) and 1-, 2-, 3-4- and 7-yr follow-up. Growth trends as a function of time relative to menarche were determined from prepuberty to early adulthood for tibial length (TL), total cross-sectional area (tCSA)…

Responses of serum androgenic-anabolic and catabolic hormones to prolonged strength training.

Endocrine and neuromuscular effects of prolonged strength training were investigated in 21 strength-trained male subjects during the course of a 24-week progressive strength training and during a subsequent detraining period of 12 weeks. Maximal isometric leg extensor force increased by 19% (P less than 0.001) during the first 20 weeks, followed by a plateau during the 4 latest weeks of training. During the course of the training period, no systematic change was found in serum testosterone concentrations, but there was a decreasing tendency in the concentrations of free testosterone (NS), 17-OH-progesterone (NS), androstenedione (P less than 0.05), dehydroepiandrosterone (P less than 0.05),…

Lower-Limb Pain, Disease, and Injury Burden as Determinants of Muscle Strength Deficit After Hip Fracture

Background: Hip fracture may result in an asymmetrical lower-limb strength deficit. The deficit may be related to the trauma, surgical treatment, pain, or disuse of the fractured limb. However, disease and injury burden or musculoskeletal pain in the other limb may reduce muscle strength on that side, reducing the asymmetrical deficit. The aim of our study was to explore the asymmetrical strength deficit and to determine the potential underlying factors in patients from six months to seven years after a hip fracture. Methods: The asymmetrical deficit was calculated ([fractured limb/sum of both lower limbs] x 100%) for isometric knee extension torque, rate of force development during isometr…

Weight-bearing, muscle loading and bone mineral accrual in pubertal girls--a 2-year longitudinal study.

Abstract Objectives: The mechanical environment is considered to be the most important determinant of bone strength. Local muscle force, in turn, is regarded as the largest source of loading applied to bones. However, the effect of weight-bearing on bone mineral accrual is unclear. Comparing the relationship between muscle force and bone mineral content (BMC) in the upper and lower limbs provides a means of investigating this issue. Subjects and methods : The study group comprised 258 healthy girls aged 10–13 years old at baseline. BMC, lean body mass (LM) and fat body mass (FM) of total body were assessed by dual-energy X-ray absorptiometry at baseline and 2 years after. The maximal isomet…

Sense of coherence: effect on adherence and response to resistance training in older people with hip fracture history.

Our aim was to study the effects of sense of coherence (SOC) on training adherence and interindividual changes in muscle strength, mobility, and balance after resistance training in older people with hip fracture history. These are secondary analyses of a 12-week randomized controlled trial of progressive resistance training in 60- to 85-year-old community-dwelling people 0.5–7 years after hip fracture (n = 45; ISRCTN34271567). Pre- and posttrial assessments included SOC, knee extension strength, walking speed, timed up-and-go (TUG), and Berg Balance Scale (BBS). Group-by-SOC interaction effects (repeated-measures ANOVA) were statistically significant for TUG (p = .005) and BBS (p = .040), …

Effects of strength and endurance training on muscle fibrecharacteristics in elderly women

The effects of 18 weeks' intensive strength and endurance training on fibre characteristics of the vastus lateralis muscle were studied in 76- to 78-year-old women. Type I and type IIa fibres constituted over 90% of the cell population and were almost equally represented. No changes were observed in the proportions of the different fibre types. When comparing the baseline and the 18-week measurements within the groups, the strength group showed a mean increase of 34% (P = 0.028) in mean type I fibre area. The frequency histograms showed an increased proportion of larger type I fibres after strength training and a decreased proportion of smaller type IIa fibres after endurance training. In t…

Differential influence of peripheral and systemic sex steroids on skeletal muscle quality in pre- and postmenopausal women

Aging is associated with gradual decline of skeletal muscle strength and mass often leading to diminished muscle quality. This phenomenon is known as sarcopenia and affects about 30% of the over 60-year-old population. Androgens act as anabolic agents regulating muscle mass and improving muscle performance. The role of female sex steroids as well as the ability of skeletal muscle tissue to locally produce sex steroids has been less extensively studied. We show that despite the extensive systemic deficit of sex steroid hormones in postmenopausal compared to premenopausal women, the hormone content of skeletal muscle does not follow the same trend. In contrast to the systemic levels, muscle t…

Normal-weight obesity and cardiometabolic risk: A 7-year longitudinal study in girls from prepuberty to early adulthood

Objective To study whether normal-weight obesity in childhood is associated with increased cardiometabolic risk in early adulthood. Methods This study assessed data for 236 girls followed from prepuberty to early adulthood. Growth chart data were obtained from birth to 18 years. Body composition was assessed by dual-energy x-ray absorptiometry and cardiometabolic risk by calculating continuous clustered risk score (at ages 11, 14, and 18). The association of body weight status with cardiometabolic risk from childhood to early adulthood was examined. Results Subjects with normal-weight obesity were virtually indistinguishable from their normal-weight lean peers in terms of relative body weig…

Variability and Symmetry of Force Platform Variables in Maximum-Speed Running in Young and Older Athletes

Eighteen young (23 ± 4 yr) and 25 older (70 ± 4 yr) male sprinters were examined for ground reaction force (GRF) and temporal-spatial variables. The data were collected during maximum-speed phase, and variability and symmetry indices were calculated from a total of 8 steps. There was little variation (CV &lt; 6%) in vertical and resultant GRF and kinematic variables, while impact loading had high variability (CV: 10–21%). Overall, the pattern of variability was similar in both groups. Yet, a small but significant age-related increase in CV was evident in horizontal GRFs. There was a variable-specific asymmetry between legs but it was not related to leg dominance. No age differences existed …

Postmenopausal hormone replacement therapy modifies skeletal muscle composition and function: a study with monozygotic twin pairs

We investigated whether long-term hormone replacement therapy (HRT) is associated with mobility and lower limb muscle performance and composition in postmenopausal women. Fifteen 54- to 62-yr-old monozygotic female twin pairs discordant for HRT were recruited from the Finnish Twin Cohort. Habitual (HWS) and maximal (MWS) walking speeds over 10 m, thigh muscle composition, lower body muscle power assessed as vertical jumping height, and maximal isometric hand grip and knee extension strengths were measured. Intrapair differences (IPD%) with 95% confidence intervals (CI) were calculated. The mean duration of HRT use was 6.9 ± 4.1 yr. MWS was on average 7% (0.9 to 13.1%, P = 0.019) and muscle…

Balance Confidence and Functional Balance in Relation to Falls in Older Persons with Hip Fracture History

PURPOSE: To investigate whether self-assessed balance confidence and functional balance are associated with falls in older persons with hip fracture history. METHODS: This study is a part of a larger study on functional capacity and exercise rehabilitation in hip fracture patients. Seventy-nine patients, operated at the local hospital for collum or trochanter fracture within one-half to 7 years, participated in the laboratory measurements. Balance confidence was assessed with Activities-specific Balance Confidence scale (ABC) and functional balance using the Berg Balance Scale (BBS). According to self-reported number of falls during the previous 6 months participants were classified as thos…

Toll-like receptor 5 in obesity: The role of gut microbiota and adipose tissue inflammation

Objective This study aimed at establishing bacterial flagellin-recognizing toll-like receptor 5 (TLR5) as a novel link between gut microbiota composition, adipose tissue inflammation, and obesity. Methods An adipose tissue microarray database was used to compare women having the highest (n = 4, H-TLR) and lowest (n = 4, L-TLR) expression levels of TLR5-signaling pathway genes. Gut microbiota composition was profiled using flow cytometry and FISH. Standard laboratory techniques were used to determine anthropometric and clinical variables. In vivo results were verified using cultured human adipocytes. Results The H-TLR group had higher flagellated Clostridium cluster XIV abundance and Firmicu…

Effects of physical and cognitive training on gait speed and cognition in older adults: A randomized controlled trial

Gait speed is a measure of health and functioning. Physical and cognitive determinants of gait are amenable to interventions, but best practices remain unclear. We investigated the effects of a 12-month physical and cognitive training (PTCT) on gait speed, dual-task cost in gait speed, and executive functions (EFs) compared with physical training (PT) (ISRCTN52388040). Community-dwelling older adults, who did not meet physical activity recommendations, were recruited (n = 314). PT included supervised walking/balance (once weekly) and resistance/balance training (once weekly), home exercises (2-3 times weekly), and moderate aerobic activity 150 min/week in bouts of >10 min. PTCT included the…

Postexercise myostatin and activin IIb mRNA levels: effects of strength training.

ABSTRACTHULMI, J. J., J. P. AHTIAINEN, T. KAASALAINEN, E. PO¨LLA¨NEN, K. HA¨KKINEN, M. ALEN, H. SELA¨NNE, V. KOVANEN,and A. A. MERO. Postexercise Myostatin and Activin IIb mRNA Levels: Effects of Strength Training. Med. Sci. Sports Exerc., Vol.39, No. 2, pp. 289–297, 2007. Purpose: Muscle hypertrophy is likely to result from the cumulative effects of repeated bouts ofresistance exercise (RE) on postexercise molecular responses. Therefore, we determined muscle growth- and regeneration-relatedmRNA expression in response to a single RE bout both before and after a strength-training (ST) period. By means of this novellongitudinal setting, we examined whether postexercise gene expression at the …

Selective muscle hypertrophy, changes in EMG and force, and serum hormones during strength training in older women.

Effects of strength training (ST) for 21 wk were examined in 10 older women (64 ± 3 yr). Electromyogram, maximal isometric force, one-repetition maximum strength, and rate of force development of the leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris (QF) and of vastus lateralis (VL), medialis (VM), intermedius (VI) and rectus femoris (RF) throughout the lengths of 3/12–12/15 (Lf) of the femur, muscle fiber proportion and areas of types I, IIa, and IIb of the VL were evaluated. Serum hormone concentrations of testosterone, growth hormone (GH), cortisol, and IGF-I were analyzed for the resting, preexercise, and postexercise conditions. After the 21-wk ST, maximal for…

Outcome comparison among working adults with centralizing low back pain: Secondary analysis of a randomized controlled trial with 1-year follow-up

Our purpose was to examine if adults with centralizing pain might achieve better treatment outcomes when treated by individually designed therapy than “given advice only to stay active”. One hundred and nineteen working adults with first or a recurrent episode of low back pain (LBP) were classified as centralizers and were randomly allocated to orthopaedic manual therapy (OMT; n=42), the McKenzie (n=48) or “advice only to stay active” (Advice-only; n=29) groups. Back and leg pain were assessed by the visual analogue scale, disability with the Roland–Morris questionnaire and functional status with an activities of daily living (ADL) index. Immediately after the treatment period, LBP decrease…

Authors’ Response: Relationship of Sex Hormones to Bone Geometric Properties and Mineral Density in Early Pubertal Girls: Use of Correlation Analyses

Leukocyte and Skeletal Muscle Telomere Length and Body Composition in Monozygotic Twin Pairs Discordant for Long-term Hormone Replacement Therapy

Estrogen-based hormone replacement therapy (HRT) may be associated with deceleration of cellular aging. We investigated whether long-term HRT has effects on leukocyte (LTL) or mean and minimum skeletal muscle telomere length (SMTL) in a design that controls for genotype and childhood environment. Associations between telomeres, body composition, and physical performance were also examined. Eleven monozygotic twin pairs (age 57.6 ± 1.8 years) discordant for HRT were studied. Mean duration of HRT use was 7.3 ± 3.7 years in the user sister, while their co-twins had never used HRT. LTL was measured by qPCR and SMTLs by southern blot. Body and muscle composition were estimated by bioimpedance an…

Fat mass accumulation compromises bone adaptation to load in finnish women: A cross-sectional study spanning three generations

Body weight and lean mass correlate with bone mass, but the relationship between fat mass and bone remains elusive. The study population consisted of 396 girls and 138 premenopausal mothers and 114 postmenopausal grandmothers of these girls. Body composition and tibial length were assessed using dual-energy X-ray absorptiometry (DXA), and bone traits were determined at the tibia using peripheral quantitative computed tomography (pQCT) in the girls at the ages of 11.2 ± 0.8, 13.2 ± 0.9, and 18.3 ± 1.0 years and in the mothers (44.7 ± 4.1 years) and grandmothers (70.7 ± 6.3 years). The values of relative bone strength index (RBSI), an index reflecting the ratio of bone strength to the load ap…

Gut-adipose tissue axis in hepatic fat accumulation in humans

Recent evidence suggests that in animals gut microbiota composition (GMC) affects the onset and progression of hepatic fat accumulation. The aim of this study was to investigate in humans whether subjects with high hepatic fat content (HHFC) differ in their GMC from those with low hepatic fat content (LHFC), and whether these differences are associated with body composition, biomarkers and abdominal adipose tissue inflammation.Hepatic fat content (HFC) was measured using proton magnetic resonance spectroscopy ((1)H MRS). Fecal GMC was profiled by 16S rRNA fluorescence in situ hybridization and flow cytometry. Adipose tissue gene expression was analyzed using Affymetrix microarrays and quant…

Endogenous Hormones, Muscle Strength, and Risk of Fall-Related Fractures in Older Women

Background. Among older people, fracture-causing fall often leads to health deterioration. The role of endogenous hormone status and muscle strength on fall-related fracture risk is unclear. This study investigates if, after adjustment for bone density, endogenous hormones and muscle strength would predict fall-related limb fracture incidence in older community-dwelling women followed-up over 10 years. Methods. As a part of a prospective population-based study, 187 75-year-old women were investigated. Serum estradiol, testosterone, sex hormone binding globulin, and dehydroepiandrosterone sulfate concentrations were analyzed, and isometric muscle strength and bone mineral density were assess…

Effects of Physical and Cognitive Training on Falls and Concern About Falling in Older Adults : Results From a Randomized Controlled Trial

Abstract Background The aim of this study is to investigate whether combined cognitive and physical training provides additional benefits to fall prevention when compared with physical training (PT) alone in older adults. Methods This is a prespecified secondary analysis of a single-blind, randomized controlled trial involving community-dwelling men and women aged 70–85 years who did not meet the physical activity guidelines. The participants were randomized into combined physical and cognitive training (PTCT, n = 155) and PT (n = 159) groups. PT included supervised and home-based physical exercises following the physical activity recommendations. PTCT included PT and computer-based cogniti…

Differences in muscle and adipose tissue gene expression and cardio-metabolic risk factors in the members of physical activity discordant twin pairs

High physical activity/aerobic fitness predicts low morbidity and mortality. Our aim was to identify the most up-regulated gene sets related to long-term physical activity vs. inactivity in skeletal muscle and adipose tissues and to obtain further information about their link with cardio-metabolic risk factors. We studied ten same-sex twin pairs (age range 50-74 years) who had been discordant for leisure-time physical activity for 30 years. The examinations included biopsies from m. vastus lateralis and abdominal subcutaneous adipose tissue. RNA was analyzed with the genome-wide Illumina Human WG-6 v3.0 Expression BeadChip. For pathway analysis we used Gene Set Enrichment Analysis utilizing…

Differences in estimates of change of bone accrual and body composition in children because of scan mode selection with the prodigy densitometer.

Abstract Girls of age 10–13 yr with Tanner stage I–III maturation status ( n = 155) were measured using the Prodigy (GE Lunar) densitometer. Bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were assessed for the whole body, lumbar spine, and proximal femur using the Thin (T) and Standard (S) scan modes at years 1 and 3 of the study. The differences obtained between the T and S mode at year 1 were 1–2% for the lumbar spine and proximal femur and 5–11% for the whole body. For those girls whose default mode changed from T at year 1 to S mode at year 3, the estimated gain in BA, BMC, and BMD was 3.4%, 7.6%, and 3.1% respectively, lower than that obtained when scanning …

Orthopaedic manual therapy, McKenzie method or advice only for low back pain in working adults: a randomized controlled trial with one year follow-up.

OBJECTIVE: To examine the effects of 2 manual therapy methods compared with one counselling session with a physiotherapist with "advice-only to stay active" for treating low back pain/leg pain and disability. DESIGN: A randomized, controlled trial with a 1-year follow-up. SUBJECTS: A total of 134 subjects with low back disorders. METHODS: Participants with acute to chronic first or recurrent low back pain, excluding those with "red flag" criteria, were assigned randomly to one of the 3 intervention groups: an orthopaedic manual therapy group (n=45), a McKenzie method group (n=52), and an "advice only to be active" group (advice-only) (n=37). Data on leg and low back pain intensity and disab…