Search results for "FITNESS"
showing 10 items of 1020 documents
Central and Peripheral Contributions to Fatigue after Electrostimulation Training
2006
Purpose: We examined the effect of 4 (WK4) and 8 wk (WK8) of neuromuscular electrical stimulation (NMES) training on both endurance time and mechanisms contributing to task failure. Methods: Ten males performed a fatiguing isometric contraction with the knee extensor muscles at 20% of maximal voluntary contraction (MVC) until exhaustion before (B), at WK4, and at WK8 of NMES training. The electromyographic (EMG) activity and muscle activation obtained under MVC were recorded before and after the fatiguing task to assess central fatigue. Torque and EMG responses obtained under electrically evoked contractions were examined before and after the fatiguing task to analyze peripheral fatigue. Re…
Neural drive preservation after detraining following neuromuscular electrical stimulation training
2006
The purpose of the study was to investigate the behaviour of the central nervous system when 5 weeks of neuromuscular electrical stimulation (NMES) training was followed by 5 weeks of detraining. Nineteen males were divided into the neuromuscular electrostimulated group (EG, n=12) and the control group (CG, n=7). The training program consisted of 15 sessions of isometric NMES over a 5-week period. The EG subjects were tested before training (PRE), after 5 weeks of NMES training (POST) and after 5 weeks of detraining (DE) while CG subjects were only tested at PRE and at POST. Soleus (SOL) and gastrocnemii (GAS) maximal H-reflex and M-wave potentials were evoked at rest (i.e., H(max) and M(ma…
Cardiorespiratory Adaptations during Concurrent Aerobic and Strength Training in Men and Women
2015
This study investigated the effects of endurance followed by strength training (ES, men n = 16; women n = 15), the reverse exercise order (SE, men n = 18, women n = 13) and concurrent endurance and strength training performed on alternating days (AD, men n = 21, women n = 18) on cardiorespiratory parameters. Peak oxygen consumption ([Formula: see text]O2peak) and oxygen consumption at sub-maximal power outputs ([Formula: see text]O2submax) of 50 to 175 Watts in men and 50 to 125 Watts in women were assessed during an incremental cycling test both before and after 24 weeks of training. Increases in [Formula: see text]O2peak in both men and women were statistically larger in AD (18±9% and 25±…
Enzyme activities and glycogen concentration in skeletal muscle in alcoholism. The effect of abstinence and physical conditioning.
1974
. Muscle metabolism of chronic alcoholics has been studied using a muscle biopsy technique immediately after a drinking period, after 6–7 days' abstinence and after one month's physical conditioning. The activities of CPK, HK, LDH, MDH and SDH were significantly decreased in musculus vastus lateralis for 1–2 days after an alcoholic debauch. The enzyme activities of the alcoholics, who either had been abstinent for 6–7 days or in addition conditioned for one month, did not differ from those of the controls. The concentration of muscle glycogen was at the same level in both groups, but in bicycle ergometer work of an equal relative intensity the alcoholics used more glycogen than the control …
Waist circumference and BMI are independently associated with the variation of cardio-respiratory and neuromuscular fitness in young adult men.
2006
To test two hypotheses: (1) cardiorespiratory (CRF) and neuromuscular (NMF) fitness is associated with body mass index (BMI) and waist circumference (WC), independent of each other and of leisure-time physical activity; (2) individuals with high CRF and NMF have lower WC for a given BMI, compared with those with low CRF and NMF. Cross-sectional study. Men participating in refresher training organized by the Finnish Defence Forces. A total of 951 men (mean age 29.1, s.d. 4.2 years; BMI 25.3 kg/m2, s.d. 3.8; WC 91, s.d. 11 cm). Body mass index, WC, maximal oxygen uptake (VO2max), height of vertical jump, number of push-ups and sit-ups during a 1-min test, static back extension endurance, isom…
Circulating IGF-I is associated with fitness and health outcomes in a population of 846 young healthy men
2011
Abstract Context Insulin-like growth factor-I (IGF-I) is thought to mediate many of the beneficial outcomes of physical activity. While IGF-I has previously been shown to be positively related with aerobic fitness, few studies have examined IGF-I relationships with other fitness and health parameters. The robustness of IGF-I as a biomarker of fitness and health has yet to be fully determined. Objective To determine the association of circulating IGF-I with fitness, body composition and health parameters in young, healthy men. Design and subjects A cross-section of 846 young, healthy Finnish men (25 ± 5 yr, 180 ± 6 cm, 81 ± 13 kg). Subjects were divided into quintiles of IGF-I concentrations…
Body Composition and Fitness during Strength and/or Endurance Training in Older Men
2008
PURPOSE: This study examined adaptations in body composition and physical fitness during a 21-wk strength and/or endurance training period in 40- to 65-yr-old men. We also compared the usefulness of different methods for the analysis of body composition to detect training-induced adaptations. METHODS: Fifty-three men were randomized into the endurance training (E: N = 14), strength training (S: N = 13), combined strength and endurance training (SE: N = 15), or control (C: N = 11) groups. S and E trained 2 and SE 2 x 2 times a week for strength and endurance. RESULTS: Percentage of fat (fat%) decreased (5-8%) similarly in all training groups. Fat% measured by DXA at baseline and its change c…
Effect of electrostimulation training-detraining on neuromuscular fatigue mechanisms.
2007
The aim of this study was to evaluate the effects of neuromuscular electrical stimulation (NMES) training and subsequent detraining on neuromuscular fatigue mechanisms. Ten young healthy men completed one NMES fatigue protocol before and after a NMES training program of 4 weeks and again after 4 weeks of detraining. Muscle fatigue (maximal voluntary torque loss), central fatigue (activation failure), and peripheral fatigue (transmission failure and contractile failure) of the plantar flexor muscles were assessed by using a series of electrically evoked and voluntary contractions with concomitant electromyographic and torque recordings. At baseline, maximal voluntary torque decreased signifi…
Recovery after Heavy Resistance Exercise and Skeletal Muscle Androgen Receptor and Insulin-Like Growth Factor-I Isoform Expression in Strength Traine…
2011
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, …
Running in highly cushioned shoes increases leg stiffness and amplifies impact loading
2018
AbstractRunning shoe cushioning has become a standard method for managing impact loading and consequent injuries due to running. However, despite decades of shoe technology developments and the fact that shoes have become increasingly cushioned, aimed to ease the impact on runners’ legs, running injuries have not decreased. To better understand the shoe cushioning paradox, we examined impact loading and the spring-like mechanics of running in a conventional control running shoe and a highly cushioned maximalist shoe at two training speeds, 10 and 14.5 km/h. We found that highly cushioned maximalist shoes alter spring-like running mechanics and amplify rather than attenuate impact loading. T…