The effects of 12-week progressive strength training on strength, functional capacity, metabolic biomarkers, and serum hormone concentrations in healthy older women : morning versus evening training

Previous findings suggest that performing strength training (ST) in the evening may provide greater benefit for young individuals. However, this may not be optimal for the older population. The purpose of this study was to compare the effects of a 12-week ST program performed in the morning vs. evening on strength, functional capacity, metabolic biomarker and basal hormone concentrations in older women. Thirty-one healthy older women (66 ± 4 years, 162 ± 4 cm, 75 ± 13 kg) completed the study. Participants trained in the morning (M) (07:30, n = 10), in the evening (E) (18:00, n = 10), or acted as a non-training control group (C) (n = 11). Both intervention groups performed whole-body strengt…

Validity and reliability of the motivation for physical activity (RM4-FM) questionnaire

There is a lack of validated instruments measuring motivation for physical activity (RM4-FM) in the Finnish language. The study examined the translated RM4-FM instrument’s psychometric properties in a sample of healthy, older Finnish adults. RM4-FM was translated and linguistically validated adhering to published guidelines. 65–75-year olds (n=102), completed the RM4-FM, the physical activity acceptance questionnaire (PAAQ) and sociodemographic characteristics questionnaires electronically. The RM4-FM was readministered one month after the initial assessment. RM4-FM translated well into Finnish. Motivation dimension scores were skewed towards high internal and low external motivation. A flo…

Acute neuromuscular and hormonal responses to 20 versus 40% velocity loss in males and females before and after 8 weeks of velocity-loss resistance training

Scientific examination of velocity-based resistance training (VBRT) has increased recently, but how males and females respond to different VBRT protocols or how these acute responses are modified after a period of training is unknown. Habitually resistance-trained males and females followed either a 20 or 40% velocity-loss programme for 8 weeks. Acute squat loading tests (five sets, 70% one-repetition maximum load, 3 min rest) were performed before and after the training period. Tests of maximum neuromuscular performance and blood sampling were conducted before, within 10 min of completion (POST) and 24 h after each acute loading test. Testing included countermovement jump, resting femoral …

Resistance exercise with different workloads have distinct effects on cellular respiration of peripheral blood mononuclear cells

Little is known how acute exercise-induced inflammation and metabolic stress affect immune cell bioenergetics and the portion of its components. Therefore, we investigated acute effects of eccentric-only (E), concentric-only (C) and combined eccentric-concentric resistance exercise (E + C) bouts on cellular respiration of peripheral blood mononuclear cells (PBMCs). Twelve strength-trained young men performed bench press resistance exercises in randomized order. Venous blood samples were drawn at pre-, 5 min post- and 24 h post-exercise. Several PBMC respiration states were measured using high-resolution respirometry. Levels of leukocytes, interleukin 6 (IL-6), C-reactive protein (CRP), crea…

Older Age Increases the Amplitude of Muscle Stretch-Induced Cortical Beta-Band Suppression But Does not Affect Rebound Strength

Healthy aging is associated with deterioration of the sensorimotor system, which impairs balance and somatosensation. However, the exact age-related changes in the cortical processing of sensorimotor integration are unclear. This study investigated primary sensorimotor cortex (SM1) oscillations in the 15–30 Hz beta band at rest and following (involuntary) rapid stretches to the triceps surae muscles (i.e., proprioceptive stimulation) of young and older adults. A custom-built, magnetoencephalography (MEG)-compatible device was used to deliver rapid (190°·s−1) ankle rotations as subjects sat passively in a magnetically-shielded room while MEG recorded their cortical signals. Eleven young (age…

Neuromuscular and hormonal responses to constant and variable resistance loadings.

Purpose: The purpose of this study was to investigate the acute effects of constant and variable resistance exercise on neuromuscular and endocrine responses during maximal strength and hypertrophic loadings. Methods: Thirteen young men (age = 28.4 ± 3.7 yr) took part in four loadings (maximal strength and hypertrophic loadings using both constant and variable resistance) in a counterbalanced order. Maximal strength loadings consisted of 15 sets of one repetition at 100% one-repetition maximum, and hypertrophic loadings consisted of five sets of 10 repetitions (initial load of 80% one-repetition maximum). Preloading, immediately postloading, 15 min postloading, and 30 min postloading tests …

Training load does not affect detraining's effect on muscle volume, muscle strength and functional capacity among older adults

Research underlines the potential of low-load resistance exercise in older adults. However, while the effects of detraining from high-load protocols have been established, it is not known whether gains from low-load training would be better/worse maintained. The current study evaluated the effects of 24weeks of detraining that followed 12weeks of high- and low-load resistance exercise in older adults. Fifty-six older adults (68.0±5.0years) were randomly assigned to leg press and leg extension training at either HIGH load (2×10-15 repetitions at 80% of one-repetition maximum (1-RM)), LOW load (1×80-100 repetitions at 20% of 1-RM), or LOW+ load (1×60 repetitions at 20% of 1-RM, immediately fo…

Power Loading-Induced Fatigue is Influenced by Menstrual Cycle Phase

Purpose To examine the effects of fatiguing power-loading on neuromuscular properties, force production, and metabolic capacities during four phases of the menstrual cycle (MC); menstruation (M), mid-follicular (mid FOL), ovulation (OV), and mid-luteal (mid LUT). Methods Sixteen eumenorrheic women performed sessions of maximal explosive leg press (2x10 at 60%1RM load with 2 min recovery between sets). Serum hormones and neuromuscular responses were measured. Results The loading protocol significantly decreased power (between -14.2% and -12.5%; p < 0.001) and maximal force production (between MVC; -15.0% and -7.8%; p < 0.001–0.05), while decreasing activation level (between AL; -6.9% and -2.…

Voimaharjoittelua ikääntyneille urheilijoille ja kuntoutujille

Säännöllinen liikunnan harrastaminen on tärkeää, eikä tärkeys vähene kun ikävuosia tulee lisää. Ikääntyessä esimerkiksi lihasvoima ja -massa hupenevat, millä on epäsuotuisa vaikutus niin urheilusuoritukseen kuin päivittäiseen elämäänkin. Liikuntatieteiden tohtori Simon Walker on useita vuosia tutkinut voimaharjoittelun vaikutuksia iäkkäämmillä aikuisilla ja tietää paljon sen suotuisista vaikutuksista niin terveyteen kuin suorituskykyynkin. Tässä artikkelissa hän kertoo tiivistetysti mitä hyötyjä painojen nostelu saa aikaan kehossa ja suorituskyvyssä, miten harjoittelussa pääsee alkuun sekä miten harjoittelu tulee toteuttaa. nonPeerReviewed

Effects of a 9-month resistance training intervention on quality of life, sense of coherence, and depressive symptoms in older adults: randomized controlled trial

Purpose (1) To determine the effects of a 9-month resistance training intervention on quality of life, sense of coherence, and depressive symptoms in older adults, and (2) to compare effects between different training frequencies. Methods Men and women aged 65–75 (N = 106) were randomized to four groups according to training frequency: training groups RT1 (n = 26), RT2 (n = 27), and RT3 (n = 28) and non-training control group (n = 25). All training groups attended supervised resistance training twice a week for 3 months. For the following 6 months, they continued training with different frequencies (1, 2 or 3 times per week). Psychological functioning was measured by quality of life (WHOQOL…

Modulations of corticospinal excitability following rapid ankle dorsiflexion in skill- and endurance-trained athletes

Abstract Purpose Long-term sports training, such as skill and endurance training, leads to specific neuroplasticity. However, it remains unclear if muscle stretch-induced proprioceptive feedback influences corticospinal facilitation/inhibition differently between skill- and endurance-trained athletes. This study investigated modulation of corticospinal excitability following rapid ankle dorsiflexion between well-trained skill and endurance athletes. Methods Ten skill- and ten endurance-trained athletes participated in the study. Corticospinal excitability was tested by single- and paired-pulse transcranial magnetic stimulations (TMS) at three different latencies following passive rapid ankl…

Neuromuscular fatigue induced by an isotonic heavy-resistance loading protocol in knee extensors.

Abstract The main aim of this study was to assess neuromuscular fatigue during a typical high-load, low-repetition loading protocol. Muscle stimulations were used to assess maximum voluntary contraction, resting single- and double-pulse twitch characteristics, and superimposed double-pulse twitch force (used to calculate voluntary activation) before and after an acute knee extension loading protocol. In our participants, who had previous resistance training experience, the mean voluntary activation level was 96.2% in an unfatigued state. Maximum voluntary contraction (−11.8%), resting double-pulse twitch force (−10.6%), and voluntary activation (−2.1%) were markedly decreased as a consequen…

WITHDRAWN: Scaling up strategies of the Chronic Respiratory Disease programme of the European Innovation Partnership on Active and Healthy Ageing (Action Plan B3 – Area 5)

Modulation of H-reflex and V-wave responses during dynamic balance perturbations

AbstractMotoneuron excitability is possible to measure using H-reflex and V-wave responses. However, it is not known how the motor control is organized, how the H-reflex and V-wave responses modulate and how repeatable these are during dynamic balance perturbations. To assess the repeatability, 16 participants (8 men, 8 women) went through two, identical measurement sessions with ~ 48 h intervals, where maximal isometric plantar flexion (IMVC) and dynamic balance perturbations in horizontal, anterior–posterior direction were performed. Soleus muscle (SOL) neural modulation during balance perturbations were measured at 40, 70, 100 and 130 ms after ankle movement by using both H-reflex and V-…

Neuromuscular adaptations to constant vs. variable resistance training in older men.

This study examined the effects of constant or variable external resistance training on neuromuscular adaptations in the lower limbs of older men. 37 subjects (age 65±4 year) were quasi-randomly assigned to the constant or variable training group, or a non-training control group. Training consisted of a 20-week medium-intensity, high volume resistance training program. Maximum bilateral concentric and isometric force production of the leg extensors as well as repetitions-to-failure test were performed pre-, mid- and post-training. Vastus lateralis muscle cross-sectional area was assessed by ultrasound and lean leg mass was assessed by dual-energy x-ray absorptiometry. Both training groups s…

Kinetic and electromyographic analysis of single repetition constant and variable resistance leg press actions

During a multi-joint leg press action, maximal force capabilities increase with increasing knee angle. In typical resistance exercises, constant resistance is used, which does not stress the neuromuscular system at large knee angles. The purpose of this study was to compare constant and variable resistance settings using a range of contraction loads and velocities. Nine healthy, untrained males performed single contractions using four different resistance settings (constant resistance, two settings that increased resistance at large knee angles and one setting that reduced resistance at large knee angles). Single contractions using 40%, 60%, and 80% of one repetition maximum with both stead…

Use of Visual Feedback During Jump-Squat Training Aids Improvement in Sport-Specific Tests in Athletes.

Vanderka, M, Bezak, A, Longova, K, Krcmar, M, and Walker, S. Use of visual feedback during jump-squat training aids improvement in sport-specific tests in athletes. J Strength Cond Res 34(8): 2250-2257, 2020-This study investigated the effects of instantaneous performance feedback during the jump-squat exercise over a 6-week training period. Twenty-five strength-trained athletes were randomly divided into an instant feedback (n = 13, half-squat 3-repetition maximum (3RM)/body mass = 2.38 ± 0.19) or a nonfeedback (n = 12, half-squat 3RM/body mass = 2.03 ± 0.44) group. Both groups performed the same training program (3 × week), consisting of 4 sets of 8 repetitions (weeks 1-3) and 8 sets of 4…

Ten-year resistance training background modulates somatosensory P3 cognitive brain resonse in older men : a magnetoencephalograpy study

The brain electrophysiological component P3, associated with good cognitive abilities, deteriorates during healthy aging. Both cognitive functions and P3 component amplitude respond positively to exercise, but the effects of resistance training on P3 are much less studied. Short-term resistance training interventions in older adults indicate modulation towards larger P3 amplitude, but this association has not been studied with a longitudinal study design. We investigated magnetoencephalographically recorded P3 (P3m) in a unique study design of nine aged men (mean age 77.7 y) with quasi-supervised resistance training background over a 10-year period and eight controls of similar age (mean ag…

Reliability of transcranial magnetic stimulation and H-reflex measurement during balance perturbation tasks

Following ankle movement, posterior balance perturbation evokes short- (SLR ∼30–50 ms), medium- (MLR ∼50–60 ms), and long-latency responses (LLR ∼70–90 ms) in soleus muscle before voluntary muscle contraction. Transcranial magnetic stimulation (TMS) and Hoffmann-reflex (H-reflex) measurements can provide insight into the contributions of corticospinal and spinal mechanisms to each response. Motor evoked potential (MEP) and H-reflex responses have shown good reliability in some dynamic muscle contraction tasks. However, it is still unclear how reliable these methods are in dynamic balance perturbation and corticospinal modulation during long amplitude balance perturbation tasks. 14 subjects …

Acute Effects of Loaded Half-Squat Jumps on Sprint Running Speed in Track and Field Athletes and Soccer Players

The purpose of the study was to determine the acute responses to a jump squat protocol designed to induce postactivation potentiation on sprint running performance in experienced track and field athletes and soccer players. Twenty-five regional level athletes (12 track and field: ∼17 years; ∼177 cm; ∼73 kg and 13 soccer: ∼18 years; ∼175 cm; ∼72 kg) performed 2 test sessions assessing 40-m sprint running performance in a balanced, crossover design. Dual-beam light timing gates measured 0-20 and 20-40 m sprint times before and after either 9 minutes of sitting (control) or 2 sets of 6 repetition half-squat jump with the load eliciting maximum power (experimental) conditions. Sprint performanc…

Strength training in endurance runners.

This study examined effects of periodized maximal versus explosive strength training and reduced strength training, combined with endurance training, on neuromuscular and endurance performance in recreational endurance runners. Subjects first completed 6 weeks of preparatory strength training. Then, groups of maximal strength (MAX, n=11), explosive strength (EXP, n=10) and circuit training (C, n=7) completed an 8-week strength training intervention, followed by 14 weeks of reduced strength training. Maximal strength (1RM) and muscle activation (EMG) of leg extensors, countermovement jump (CMJ), maximal oxygen uptake (VO(2MAX)), velocity at VO(2MAX) (vVO(2MAX)) running economy (RE) and basal…

Evidence of resistance training-induced neural adaptation in older adults

The deleterious effects of aging on force production are observable from the age of 40 upwards, depending on the measure. Neural mechanisms contributing to maximum force production and rate of force development have been suggested as descending drive from supraspinal centers, spinal motoneuron excitability, and corticospinal inhibition of descending drive; all of which influence motor unit recruitment and/or firing rate. Resistance-trained Master athletes offer a good source of information regarding the inevitable effects of aging despite the countermeasure of systematic resistance-training. However, most evidence of neural adaptation is derived from longitudinal intervention studies in pre…

Neomuscular fatigue to power loading using a weight-stack device fitted with or without additional rubber band resistance

The addition of a rubber band (RB) to traditional weight-based resistance may be beneficial regarding the deceleration phase common during explosive power actions with light weights. This would lead to greater force and muscle activity during the latter part of the movement, but this may influence the distribution of neuromuscular fatigue. Fifteen men performed 2 knee extension power loadings (5 × 5 × 40% of 1 repetition maximum [1RM]) using a typical weight-stack device without (WS) and with the addition of a RB (WS + RB) in a crossover design. Concentric contractions were performed as fast as possible, and analyzed for torque, velocity, power, and vastus lateralis and medialis surface ele…

Maximum Dynamic Lower-Limb Strength Was Maintained During 24-Week Reduced Training Frequency in Previously Sedentary Older Women.

Walker, S, Serrano, J, and Van Roie, E. Maximum dynamic lower-limb strength was maintained during 24-week reduced training frequency in previously sedentary older women. J Strength Cond Res 32(4): 1063-1071, 2018-There is little study into the effects of reducing strength training below the recommended twice weekly frequency, particularly in older women, despite the possibility that individuals will encounter periods of reduced training frequency. The purpose of the present study was to determine the effects of a period of reduced training frequency on maximum strength and muscle mass of the lower limbs in comparison with the recommended training frequency of twice per week. After an initia…

Body composition in 18 to 88-year-old adults - comparison of multifrequency bioimpedance and dual-energy X-ray absorptiometry

Objective -- This study compared bioimpedance analysis (BIA) in the assessment of body composition with dual-energy X-ray absorptiometry (DXA) in 18- to 88-year-old adults. Design and Methods -- Body composition of 882 adults was estimated by eight-polar BIA and DXA. In addition, estimates of lean mass, fat mass, and percentage of fat were investigated across a range of age and leisure time physical activity (LTPA) groups. Results -- Compared to DXA, larger lean masses (mean difference 2.9 and 1.6 kg) and smaller fat masses (3.1 and 2.6 kg) were estimated by BIA in both women and men, respectively. Differences between the methods' mean values were evident in all age and LTPA groups, except …

Resistance Training Induces Antiatherogenic Effects on Metabolomic Pathways

Introduction: Arising evidence suggests that resistance training has the potential to induce beneficial modulation of biomarker profile. To date, however, only immediate responses to resistance training have been investigated using high-throughput metabolomics whereas the effects of chronic resistance training on biomarker profile have not been studied in detail. Methods: A total of 86 recreationally active healthy men without previous systematic resistance training background were allocated into i) a resistance training (RT) group (n=68, age 33 ± 7 years, body mass index (BMI) 28 ± 3 kg/m2 ) and ii) a non-RT group (n=18, age 31 ± 4 years, BMI 27 ± 3 kg/m2 ). Blood samples were collected at…

Acute neuromuscular and hormonal responses and long-term adaptations to hypertrophic resistance training : with special reference to constant versus variable resistance

Similar increases in strength after short-term resistance training due to different neuromuscular adaptations in young and older men

This study investigated whether differences in neuromuscular performance and muscle hypertrophy occur between young and older men. Twenty-three young (29 ± 9 years) and 26 older men (64 ± 8 years) completed 10 weeks of high-volume, medium load “hypertrophic” resistance training with low frequency (twice per week) with 10 young (34 ± 11 years) and 11 older men (65 ± 3 years) acting as nontraining control subjects. Training consisted of 2–5 sets of 8–14 repetitions (1- to 2-minute rest). Lower-limb dynamic (leg press) and isometric maximum leg extension force, as well as lower-limb lean mass and vastus lateralis cross-sectional area were assessed before and after the training period. Training…

Effects of Upper Body Eccentric versus Concentric Strength Training and Detraining on Maximal Force, Muscle Activation, Hypertrophy and Serum Hormones in Women

Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were mea…

Cortical Proprioceptive Processing Is Altered by Aging

Proprioceptive perception is impaired with aging, but little is known about aging-related deterioration of proprioception at the cortical level. Corticokinematic coherence (CKC) between limb kinematic and magnetoencephalographic (MEG) signals reflects cortical processing of proprioceptive afference. We, thus, compared CKC strength to ankle movements between younger and older subjects, and examined whether CKC predicts postural stability. Fifteen younger (range 18-31 years) and eight older (66-73 years) sedentary volunteers were seated in MEG, while their right and left ankle joints were moved separately at 2 Hz (for 4 min each) using a novel MEG-compatible ankle-movement actuator. Coherence…

Isometric parameters in the monitoring of maximal strength, power, and hypertrophic resistance-training.

This study monitored strength-training adaptations via isometric parameters throughout 2 × 10 weeks of hypertrophic (HYP I–II) or 10 weeks maximum strength (MS) followed by 10 weeks power (P) training with untrained controls. Trainees performed bilateral isometric leg press tests analyzed for peak force (maximal voluntary contraction (MVC)) and rate of force development (RFD) every 3.5 weeks. These parameters were compared with dynamic performance, voluntary and electrically induced isometric contractions, muscle activity, and cross-sectional area (CSA) in the laboratory before and after 10 and 20 weeks. RFD increased similarly during the first 7 weeks (HYP I, 44% ± 53%; MS, 48% ± 55%, P &l…

Physical qualities and body composition predictors of running performance in national level women’s official soccer matches

The purpose of the study was to (1) determine match running performance, anthropometry and various physical qualities of national level women soccer players and (2) identify key physical qualities and anthropometric predictors of match running profile during a competitive season. Twenty-five national level Finnish soccer players participated in the study. Players performed countermovement jump, loaded squat jumps, 30-meter sprint, maximum isokinetic knee flexor and extensor contractions, an incremental treadmill test and underwent body composition assessment in the lab. Match running performance was analyzed from 115 match observations during competitive league matches over 11 weeks after t…

Strength Training Improves Metabolic Health Markers in Older Individual Regardless of Training Frequency

The main purpose of the present study was to investigate the effect of frequency, thereby increasing training volume, of resistance training on body composition, inflammation markers, lipid and glycemic profile in healthy older individuals (age range 65–75 year). Ninety-two healthy participants were randomly assigned to one of four groups; performing strength training one- (EX1), two- (EX2), or three- (EX3) times-per-week and a non-training control (CON) group. Whole-body strength training was performed using 2–5 sets and 4–12 repetitions per exercise and 7–9 exercises per session. All training groups attended supervised resistance training for 6 months. Body composition was measured by dua…

Aging and strength training influence knee extensor intermuscular coherence during low- and high-force isometric contractions

Aging is associated with reduced maximum force production and force steadiness during low-force tasks, but both can be improved by training. Intermuscular coherence measures coupling between two peripheral surface electromyography (EMG) signals in the frequency domain. It is thought to represent the presence of common input to alpha-motoneurons, but the functional meaning of intermuscular coherence, particularly regarding aging and training, remain unclear. This study investigated knee extensor intermuscular coherence in previously sedentary young (18–30 years) and older (67–73 years) subjects before and after a 14-week strength training intervention. YOUNG and OLDER groups performed maximu…

Acute responses of comprehensive gonadosteroids and corticosteroids to resistance exercise before and after 10 weeks of supervised strength training

New Findings: What is the central question of this study? Although acute responses of the principal gonadosteroid and corticosteroid hormones to resistance exercise are well documented, there is no information regarding how the key lower-concentration intermediary hormones respond and potentially influence these hormonal pathways. What is the main finding and its importance? This study provides evidence for cascading conversions of some gonadosteroids, and the data suggest that the testosterone concentration increases independently of these hormones. These findings challenge future studies to determine the exact physiological roles of the lower-concentration gonadosteroids and corticosteroi…

Water immersion methods do not alter muscle damage and inflammation biomarkers after high-intensity sprinting and jumping exercise

Purpose The aim of this study was to compare the efficacy of three water immersion interventions performed after active recovery compared to active recovery only on the resolution of inflammation and markers of muscle damage post-exercise. Methods Nine physically active men (n = 9; age 20‒35 years) performed an intensive loading protocol, including maximal jumps and sprinting on four occasions. After each trial, one of three recovery interventions (10 min duration) was used in a random order: cold-water immersion (CWI, 10 °C), thermoneutral water immersion (TWI, 24 °C), contrast water therapy (CWT, alternately 10 °C and 38 °C). All of these methods were performed after an active recovery (1…

Older adults show elevated intermuscular coherence in eyes‐open standing but only young adults increase coherence in response to closing the eyes

New Findings: What is the central question of this study? Can a 14-week strength-training programme modify intermuscular coherence levels during bipedal standing tasks with eyes open and eyes closed and reduce age-related differences? What is the main finding and its importance? Older adults had more prominent common input over 4–14 Hz with eyes open, but during the eyes-closed task the young adults were able to further enhance their common input at 6–36 Hz. This indicates that young adults are better at modulating common input in different motor tasks. Abstract: Understanding neural control of standing balance is important to identify age-related degeneration and design interventions to ma…

Esteetön rakentaminen on kaunista ja käytännöllistä

Motivational characteristics and resistance training in older adults: A randomized controlled trial and 1-year follow-up

The aim of this study was to investigate the effects of a 9‐month supervised resistance training intervention on motivational and volitional characteristics related to exercise, and whether the absolute level and/or intervention‐induced change in these characteristics predict self‐directed continuation of resistance training 1 year after the intervention. Community dwelling older adults aged 65‐75, who did not fulfill physical activity recommendations, were randomized into resistance training intervention groups: training once‐ (n = 26), twice‐ (n = 27), three‐times‐a‐week (n = 28) or non‐training control group (n = 25). Training groups participated in supervised resistance training for 9 m…

Acute elevations in serum hormones are attenuated after chronic training with traditional isoinertial but not accentuated eccentric loads in strength‐trained men

It has been proposed that the maintenance of acute hormonal responses reveal an efficacy of a training stimulus to evoke ongoing increases in strength and muscle mass. We previously observed that maximum strength continued to improve throughout a 10‐week period in an accentuated eccentric loading group (AEL) but not a traditional isoinertial loading (ISO) group. Therefore, this study investigated whether the magnitude of acute hormonal responses was greater (i.e., maintained) in AEL compared to ISO at the end of the training period. Subjects in AEL (eccentric load = concentric load + 40%) and ISO performed experimental loading tests (three sets of 10 repetitions in the leg press and knee ex…

Neuromuscular fatigue during dynamic maximal strength and hypertrophic resistance loadings

The purpose of this study was to compare the acute neuromuscular fatigue during dynamic maximal strength and hypertrophic loadings, known to cause different adaptations underlying strength gain during training. Thirteen healthy, untrained males performed two leg press loadings, one week apart, consisting of 15 sets of 1 repetition maximum (MAX) and 5 sets of 10 repetition maximums (HYP). Concentric load and muscle activity, electromyography (EMG) amplitude and median frequency, was assessed throughout each set. Additionally, maximal bilateral isometric force and muscle activity was assessed pre-, mid-, and up to 30 min post-loading. Concentric load during MAX was decreased after set 10 (P<0…

Resistance training status modifies inflammatory response to explosive and hypertrophic resistance exercise bouts.

The purpose of the present study was to examine the immediate and prolonged immune response in circulating cytokine and adipocytokine concentrations after two different resistance exercise bouts: hypertrophic (HYP1, 5 × 10, 80% of 1RM) and maximal explosive (POW1, 10 × 5, 60% of 1RM) resistance exercise bouts and how 12 weeks of resistance training (RT) modifies these responses (HYP2, POW2). Eight men completed the study. RE-induced interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-1 receptor antagonist (IL-1ra), monocyte-chemoattractant protein-1 (MCP-1), leptin, resistin, and adiponectin were measured before (PRE) and immediately (POST0), 24 (POST24) and 48 (POST48) hours after RE…

Effects of prolonged hypertrophic resistance training on acute endocrine responses in young and older men.

The present study investigated changes in acute serum hormone responses to a resistance exercise bout following a prolonged period of hypertrophic resistance training in young (YM) and older men (OM). Subjects performed a 5 × 10RM leg press exercise protocol before and after 20 weeks of hypertrophic resistance training. In YM, the acute responses in growth hormone were greater compared with before training (p &lt; .05), and cortisol concentration did not increase after training. Endocrine responses in OM were similar before and after training. Greater acute growth hormone responses after training were associated with larger gains in lean mass in the entire subject group (r = .596, p = .019)…

Effects of different strength training frequencies on maximum strength, body composition and functional capacity in healthy older individuals

There is controversy in the literature regarding the dose-response relationship of strength training in healthy older participants. The present study determined training frequency effects on maximum strength, muscle mass and functional capacity over 6 months following an initial 3-month preparatory strength training period. One-hundred and six 64–75 year old volunteers were randomly assigned to one of four groups; performing strength training one (EX1), two (EX2), or three (EX3) times per week and a non-training control (CON) group. Whole-body strength training was performed using 2–5 sets and 4–12 repetitions per exercise and 7–9 exercises per session. Before and after the intervention, ma…

Neural Adaptations to Strength Training

Scientific study of strength training has revealed numerous physiological mechanisms that contribute to: (1) acute fatigue from a single strength training session and (2) chronic adaptation to repetitive and systematic strength training. Therefore, the purpose of this chapter is initially to discuss potential neural mechanisms that influence force production from the perspective of a single repetition. Thereafter, the chapter will highlight scientific evidence for candidate neural mechanisms that acutely limit force production during a single strength training session and long-term adaptations caused by strength training. For some of these potential neural mechanisms, there is strong scient…

Increased fascicle length but not patellar tendon stiffness after accentuated eccentric-load strength training in already-trained men

Purpose This study examined whether additional external load during the eccentric phase of lower limb strength training exercises led to greater adaptations in knee extensor strength, muscle architecture, and patellar tendon properties than traditional concentric–eccentric training in already-trained men. Methods Twenty-eight men accustomed to strength training were randomized to undertake 10 weeks of supervised traditional (TRAD) or accentuated eccentric loading (AEL) or continue their habitual unsupervised (CON) strength training. TRAD and AEL trained 2∙week−1 with a six-repetition maximum (RM) session and a ten-RM session. TRAD used the same external load in both concentric and eccentric…

Effects of resistance training frequency on cardiorespiratory fitness in older men and women during intervention and follow-up.

This study investigated the effects of resistance training (RT) performed with different frequencies, including a follow-up period, on cardiorespiratory fitness in healthy older individuals. Eighty-eight men and women (69 ± 3 years, 167 ± 9 cm and 78 ± 14 kg) were randomly placed into four groups: training one- (M1 = 11, W1 = 12), two- (M2 = 7, W2 = 14), or three- (M3 = 11, W3 = 13) times-per-week or a non-training control group (MCon = 11, WCon = 9). During months 1–3, all subjects trained two-times-per-week while during the subsequent 6 months, training frequency was set according to the group. Oxygen consumption (cycling economy: CE), gross efficiency (GE), blood lactate concentrations (…

Improved Maximum Strength, Vertical Jump and Sprint Performance after 8 Weeks of Jump Squat Training with Individualized Loads

The purpose of the study was to determine the effects of 8 weeks of jump squat training on isometric half squat maximal force production (Fmax) and rate of force development over 100ms (RFD100), countermovement jump (CMJ) and squat jump (SJ) height, and 50 m sprint time in moderately trained men. Sixty eight subjects (~21 years, ~180 cm, ~75 kg) were divided into experimental (EXP; n = 36) and control (CON, n = 32) groups. Tests were completed pre-, mid- and post-training. EXP performed jump squat training 3 times per week using loads that allowed all repetitions to be performed with ≥90% of maximum average power output (13 sessions with 4 sets of 8 repetitions and 13 sessions with 8 sets o…

An age-adapted plyometric exercise program improves dynamic strength, jump performance and functional capacity in older men either similarly or more than traditional resistance training

Power declines at a greater rate during ageing and is more relevant for functional deterioration than either loss of maximum strength or muscle mass. Human movement typically consists of stretch-shortening cycle action. Therefore, plyometric exercises, using an eccentric phase quickly followed by a concentric phase to optimize power production, should resemble daily function more than traditional resistance training, which primarily builds force production capacity in general. However, it is unclear whether older adults can sustain such high-impact training. This study compared the effects of plyometric exercise (PLYO) on power, force production, jump and functional performance to tradition…

Vain yksi voimaharjoitus viikossa riittää toimintakyvyn ylläpitämiseen ikääntyneillä

Tutkimuksella selvitimme, parantaako voimaharjoittelu iäkkäiden toimintakykyä, ja onko harjoitusmäärillä vaikutusta toimintakyvyn muutoksiin. Tutkimukseen osallistui 106 koehenkilöä (65–75 v.), jotka satunnaistettiin neljään ryhmään: 1x/vko (H1, n=26), 2x/vko (H2, n=27) ja 3x/vko (H3, n=28) harjoitteleviin ja kontrolliryhmään (K, n=25). Ensimmäisen kolmen kuukauden ajan kaikki harjoitteluryhmät voimaharjoittelivat valvotusti kahdesti viikossa (H, n=81), jonka jälkeen ryhmät harjoittelivat kuusi kuukautta (3 kk–9 kk) nimensä mukaisesti kerran, kahdesti tai kolmesti viikossa. Koehenkilöille suoritettiin testit 0 kk, 3 kk ja 9 kk. Toimintakykyä testattiin etuperinkävelyllä (E), takaperinkävely…

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition) 1

Contains fulltext : 232759.pdf (Publisher’s version ) (Closed access) In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to…

Test-retest reliability of motor-evoked potentials at 20% and 60% of maximum isometric voluntary contraction in rectus femoris muscle

Allergic Rhinitis and its Impact on Asthma (ARIA) Phase 4 (2018): Change management in allergic rhinitis and asthma multimorbidity using mobile technology

Allergic Rhinitis and its Impact on Asthma (ARIA) has evolved from a guideline by using the best approach to integrated care pathways using mobile technology in patients with allergic rhinitis (AR) and asthma multimorbidity. The proposed next phase of ARIA is change management, with the aim of providing an active and healthy life to patients with rhinitis and to those with asthma multimorbidity across the lifecycle irrespective of their sex or socioeconomic status to reduce health and social inequities incurred by the disease. ARIA has followed the 8-step model of Kotter to assess and implement the effect of rhinitis on asthma multimorbidity and to propose multimorbid guidelines. A second c…

Resistance Training Induces Antiatherogenic Effects on Metabolomic Pathways

INTRODUCTION Arising evidence suggests that resistance training has the potential to induce beneficial modulation of biomarker profile. To date, however, only immediate responses to resistance training have been investigated using high-throughput metabolomics whereas the effects of chronic resistance training on biomarker profile have not been studied in detail. METHODS A total of 86 recreationally active healthy men without previous systematic resistance training background were allocated into (i) a resistance training (RT) group (n = 68; age, 33 ± 7 yr; body mass index, 28 ± 3 kg·m) and (ii) a non-RT group (n = 18; age, 31 ± 4 yr; body mass index, 27 ± 3 kg·m). Blood samples were collecte…

Acute Neuromuscular and Hormonal Responses to Power, Strength, and Hypertrophic Protocols and Training Background

This study investigated how two slightly different athlete groups would differ in acute neuromuscular and endocrine responses to specific resistance exercise loadings and recovery compared to untrained participants. Power athletes (PA, n = 8), strength athletes (SA, n = 8) and non-athletes (NA, n = 7) performed power (PL, 7 × 6 × 50% of 1RM), maximal strength (MSL, 7 × 3 × 3RM), and hypertrophic (HL, 5 × 10 × 10RM) loadings in Smith-machine back-squat. Neuromuscular performance, serum testosterone, growth hormone, and cortisol concentrations, and blood lactate (BL) were measured before (Pre), at Mid and after (Post) loading, and after recovery for 24 and 48 h. All loadings led to acute decr…

Validity of Using Velocity to Estimate Intensity in Resistance Exercises in Men and Women

AbstractThis study aimed to examine the validity of using bar velocity to estimate relative load in squat and bench-press exercises for both young men and women. Twenty-five men and 25 women performed a progressive loading test up to 1-RM in the squat and bench-press exercises, which were repeated after 2-weeks. Relationships between mean propulsive velocity and%1-RM were analysed. A second-order polynomial equation for predicting the corresponding velocity of each percentage of 1-RM was developed for men (validation). This equation was then applied in women (cross-validation). Moreover, a specific equation for women was developed (validation) and was also applied in a sub-sample of women (…

Movement characteristics during customized exergames after total knee replacement in older adults

Introduction: There is limited understanding of how older adults can reach kinematic goals in rehabilitation while performing exergames and conventional exercises, and how similar or different the kinematics during exergaming are when compared with conventional therapeutic exercise with similar movement. The aim of this study was to describe the movement characteristics performed during exercise in custom-designed exergames and conventional therapeutic exercises among patients who have undergone unilateral total knee replacement (TKR). In addition, the secondary aim was to assess the relation of these exercise methods, and to assess participants' perceived exertion and knee pain during exer…

The order effect of combined endurance and strength loadings on force and hormone responses: effects of prolonged training

Purpose To examine acute responses and recovery of force and serum hormones to combined endurance and strength loadings utilizing different orders of exercises before and after training. Methods Physically active men were matched to an order sequence of endurance followed by strength (E + S, n = 12) or strength followed by endurance (S + E, n = 17). The subjects performed one experimental loading consisting of steady-state cycling and a leg press protocol before and after 24 weeks of order-specific combined training. Results No between-group difference in acute reductions of force was observed at week 0 (E + S −23 %, p < 0.001; S + E −22 %, p < 0.01) and 24 (E + S −25 %, p < 0.001; S + E −2…

Jump Height from Inertial Recordings : A Tutorial for a Sports Scientist

Jump performance provides meaningful information both for sporting and clinical needs. Current state-of-the-art in jump performance assessment is laboratory-bound, however, out-of-the-laboratory methods are desirable. Therefore, the purposes of the present investigation were 1) to explore whether utilising a novel analytical approach minimises the bias between inertial recording unit (IMU)-based and jump mat-based jump height estimates, and 2) to provide a thorough tutorial for a sport scientist (see appendix) to facilitate standardisation of jump height estimation. Forty one women, men and boys aged 6 to 77 years-of-age completed three maximal counter movement jumps without arm swing, whic…

Molecular signaling in muscle is affected by the specificity of resistance exercise protocol

Mammalian target of rapamycin and mitogen-activated protein kinase (MAPK) signaling pathways have been highlighted as important for muscle adaptations and thus, they may distinguish adaptations to different exercises. Typically, resistance exercise designed for muscle hypertrophy has moderate intensity (60-80% of one repetition maximum, 1 RM) while one prioritizing maximal strength with minor hypertrophy has a higher intensity (≥90% of 1 RM). Eight untrained men (28.4 ± 3.7 years) conducted two different bilateral leg press exercise protocols: hypertrophic (5 × 10 RM) and pure maximal strength (15 × 1 RM) in a counterbalanced, cross-over design with 1 week between exercises. Vastus laterali…

Moderate-Load Muscular Endurance Strength Training Did Not Improve Peak Power or Functional Capacity in Older Men and Women

The present study determined the effects of muscular endurance strength training on maximum strength and power, functional capacity, muscle activation and hypertrophy in older men and women. Eighty-one men and women acted as an intervention group while 22 acted as non-training controls (age range 64–75 y). Intervention training included super-sets (i.e., paired exercises, immediately performing the second exercises following completion of the first) with short rest intervals (30–60 s between sets) at an intensity of 50–60% one-repetition maximum (1-RM) for 15–20 repetitions. Concentric leg press actions measured maximum strength (1-RM) and concentric peak power. Functional capacity was asse…

Acute neuromuscular and hormonal responses during contrast loading: Effect of 11 weeks of contrast training

The purpose of this study was to assess (1) acute neuromuscular and endocrine responses during a contrast loading protocol and (2) how these acute responses are possibly influenced by 11 weeks of contrast training. Contrast loading tests consisting of 4 sets of 80% 1 RM back squat and 4 sets of squat jump (SJ) were performed before and after training. Bilateral isometric leg extension (LE) assessed the impact of loading on isometric variables pre-, mid-, and post-loading. Potentiated SJ performance was observed in set 2 (4.6%, P<0.05), before training only. Greater indications of fatigue were observed in SJ, isometric force, and vastus lateralis (VL) activation after training (P<0.05). Trai…

Older Age Increases the Amplitude of Muscle Stretch-Induced Cortical Beta-Band Suppression But Does not Affect Rebound Strength

Healthy aging is associated with deterioration of the sensorimotor system, which impairs balance and somatosensation. However, the exact age-related changes in the cortical processing of sensorimotor integration are unclear. This study investigated primary sensorimotor cortex (SM1) oscillations in the 15–30 Hz beta band at rest and following (involuntary) rapid stretches to the triceps surae muscles (i.e., proprioceptive stimulation) of young and older adults. A custom-built, magnetoencephalography (MEG)-compatible device was used to deliver rapid (190°·s−1) ankle rotations as subjects sat passively in a magnetically-shielded room while MEG recorded their cortical signals. Eleven young (age…

Dataset for: ACUTE ELEVATIONS IN SERUM HORMONES ARE ATTENUATED AFTER CHRONIC TRAINING WITH TRADITIONAL ISOINERTIAL BUT NOT ACCENTUATED ECCENTRIC LOADS IN STRENGTH-TRAINED MEN

It has been proposed that the maintenance of acute hormonal responses reveal an efficacy of a training stimulus to evoke ongoing increases in strength and muscle mass. We previously observed that maximum strength continued to improve throughout a 10-week period in an accentuated eccentric loading group (AEL) but not a traditional isoinertial loading (ISO) group. Therefore, the present study investigated whether the magnitude of acute hormonal responses was greater (i.e. maintained) in AEL compared to ISO at the end of the training period. Subjects in AEL (eccentric load = concentric load + 40%) and ISO performed experimental loading tests (3 sets of 10 repetitions in the leg press and knee …