Search results for "liha"
showing 10 items of 620 documents
Handgrip Strength Cannot Be Assumed a Proxy for Overall Muscle Strength
2018
OBJECTIVES: Dynapenia, low muscle strength, is predictive for negative health outcomes and is usually expressed as handgrip strength (HGS). Whether HGS can be a proxy for overall muscle strength and whether this depends on age and health status is controversial. This study assessed the agreement between HGS and knee extension strength (KES) in populations differing in age and health status.DESIGN: Data were retrieved from 5 cohorts.SETTING AND PARTICIPANTS: Community, geriatric outpatient clinics, and a hospital. Five cohorts (960 individuals, 49.8% male) encompassing healthy young and older individuals, geriatric outpatients, and older individuals post hip fracture were included.MEASURES: …
The role of physical activity and exercise in obesity and weight management: Time for critical appraisal
2016
The prevalence of overweight and obesity has increased dramatically during last 3 decades with devastating consequences to public health. Recommended strategies to reduce obesity have focused on healthier diet and physical activity (PA). Clearly, these approaches have not been successful, but whether this is due to failure to restrict energy intake or to maintain high levels of energy expenditure has been the subject of great controversy. Consequently, there has been a great deal of confusion about the role of PA and exercise in obesity and weight management. In this article, the theoretical basis for considering reduced PA and energy expenditure as the cause of obesity is appraised. Furthe…
Effect of footwear on intramuscular EMG activity of plantar flexor muscles in walking
2020
One of the purposes of footwear is to assist locomotion, but some footwear types seem to restrict natural foot motion, which may affect the contribution of ankle plantar flexor muscles to propulsion. This study examined the effects of different footwear conditions on the activity of ankle plantar flexors during walking. Ten healthy habitually shod individuals walked overground in shoes, barefoot and in flip-flops while fine-wire electromyography (EMG) activity was recorded from flexor hallucis longus (FHL), soleus (SOL), and medial and lateral gastrocnemius (MG and LG) muscles. EMG signals were peak-normalised and analysed in the stance phase using Statistical Parametric Mapping (SPM). We f…
The effects of active vs. passive recovery on riding performance during a simulated motocross race
2021
Aims: Motocross consists of two races of 30 min with a break in between. Recovery between races is paramount to performance, this study aimed to compare the effects of active and passive recovery between motocross races on riding performance. Methods: Thirteen elite and non-elite racers performed two races of 30 min with 1 h break, twice with two-week interval. Between the races active (20 min ergometer cycling at 60% of HRmax) or passive recovery (no activity) were executed in a randomized order. Lap times, heart rate during riding, blood lactate, reaction time, handgrip strength, upper back pull strength, counter movement jump height, and medicine ball throw distance were measured before …
The Effects of Restriction Pressures on the Acute Responses to Blood Flow Restriction Exercise
2019
Purpose: No current guidelines or recommendations exist informing the selection of restriction pressure during blood flow restriction exercise (BFRE). Moreover, the effects of specific relative restriction pressures on the acute muscle, metabolic and cardiopulmonary responses to BFRE are unclear. The purpose of this study was to characterize these acute responses at different levels of restriction pressure. Methods: Participants (n = 10) completed rhythmic isometric knee extension exercise across five experimental trials in a balanced randomized order. Three were BFRE trials {B-40 [restriction pressure set to 40% LOP (total limb occlusion pressure)]; B-60 (60% LOP); and B-80 (80% LOP)) with…
Musculoskeletal examination in young athletes and non-athletes:the Finnish Health Promoting Sports Club (FHPSC) study
2018
ObjectivesTo determine the inter-rater repeatability of a musculoskeletal examination and to compare findings between adolescent athletes and non-athletes in Finland.MethodsIn this cross-sectional study, a musculoskeletal examination assessing posture, mobility and movement control was carried out by a sports and exercise medicine physician on 399 athletes aged 14–17 years and 177 non-athletes. Within 2 weeks another sports and exercise medicine physician repeated the examination for 41 adolescents to test the inter-rater repeatability.ResultsIn total, 10 of the 11 tests performed had at least moderate inter-rater reliability (κ ≥0.4 or percentage agreement >80%). Athletes more often tha…
Effects of military basic training on VO2max, body composition, muscle strength and neural responses in conscripts of different aerobic condition
2019
Summary Study aim: The purpose of this study was to evaluate neuromuscular adaptations in conscripts with different fitness levels (VO2max) during 8 weeks of military basic training (BT). Material and methods: Twenty-four male conscripts (18–21 years) were divided into two groups (Good Fitness [GF] and Low fitness [LF]) based on their VO2max at the beginning of BT. Body mass (BM), fat free mass (FFM) and Fat% were measured after 2, 4, and 7 weeks of training. VO2max, maximal isometric leg press force (MVC), H-reflex (Hmax/Mmax) at rest and V-wave (V/Mmax) during maximal isometric plantarflexion were measured from the soleus muscle at the beginning, after 5, and after 8 weeks of training. Re…
Stimuli and sensors that initiate skeletal muscle hypertrophy following resistance exercise
2018
One of the most striking adaptations to exercise is the skeletal muscle hypertrophy that occurs in response to resistance exercise. A large body of work shows that a mammalian target of rapamycin complex 1 (mTORC1)-mediated increase of muscle protein synthesis is the key, but not sole, mechanism by which resistance exercise causes muscle hypertrophy. While much of the hypertrophy signaling cascade has been identified, the initiating, resistance exercise-induced and hypertrophy-stimulating stimuli have remained elusive. For the purpose of this review, we define an initiating, resistance exercise-induced and hypertrophy-stimulating signal as “hypertrophy stimulus,” and the sensor of such a s…
60-Hour Sleep Deprivation Affects Submaximal but Not Maximal Physical Performance
2018
The effect of 60-h sleep deprivation (SD) on physical performance and motor control was studied. Twenty cadets were measured for aerobic performance (VO2) before and immediately after the SD period. Maximal strength and EMG of the knee extensor muscles were measured before and after 60 h of SD. Balance, reaction times and motor control were assessed every evening and morning during the SD period. Main effects were observed for heart rate (p = 0.002, partial eta squared: 0.669), VO2 (p = 0.004, partial eta squared: 0.621), ventilation (p = 0.016, partial eta squared: 0.049), and lactate concentration (p = 0.022, partial eta squared: 0.501), whereas RER remained unaltered (p = 0.213, partial …
Muscle Free Fatty-Acid Uptake Associates to Mechanical Efficiency During Exercise in Humans
2018
Intrinsic factors related to muscle metabolism may explain the differences in mechanical efficiency (ME) during exercise. Therefore, this study aimed to investigate the relationship between muscle metabolism and ME. Totally 17 healthy recreationally active male participants were recruited and divided into efficient (EF; n = 8) and inefficient (IE; n = 9) groups, which were matched for age (mean ± SD 24 ± 2 vs. 23 ± 2 years), BMI (23 ± 1 vs. 23 ± 2 kg m−2), physical activity levels (3.4 ± 1.0 vs. 4.1 ± 1.0 sessions/week), and V˙O2peak (53 ± 3 vs. 52 ± 3 mL kg−1 min−1), respectively, but differed for ME at 45% of V˙O2peak intensity during submaximal bicycle ergometer test (EF 20.5 ± 3.5 vs. I…