Search results for "Skeletal"
showing 10 items of 3025 documents
Changes in corticospinal excitability during an acute bout of resistance exercise in the elbow flexors
2014
Purpose Hypertrophic resistance exercise (HRE) induces central and peripheral fatigue. However, more detailed information about changes in corticospinal excitability remains to be elucidated. Methods Eleven volunteers participated in the upper arm HRE which included one repetition maximum (1 RM) control contractions and three sets of 13 RM (SET1–3). Transcranial magnetic stimulation (TMS) was applied during maximal isometric voluntary contraction (MVC) at the end of each set and during control contractions to study changes in corticospinal excitability. Electrical stimulation was used in order to measure peripheral changes. Results MVC decreased after each set when compared to control contr…
Muscle mechanical properties of strength and endurance athletes and changes after one week of intensive training
2015
The study investigates whether tensiomyography (TMG) is sensitive to differentiate between strength and endurance athletes, and to monitor fatigue after either one week of intensive strength (ST) or endurance (END) training. Fourteen strength (24.1±2.0years) and eleven endurance athletes (25.5±4.8years) performed an intensive training period of 6days of ST or END, respectively. ST and END groups completed specific performance tests as well as TMG measurements of maximal radial deformation of the muscle belly (Dm), deformation time between 10% and 90% Dm (Tc), rate of deformation development until 10% Dm (V10) and 90% Dm (V90) before (baseline), after training period (post1), and after 72h o…
Muscle strength in healthy people and in patients suffering from recent-onset inflammatory arthritis.
1995
Neuromuscular function was compared among 20 patients with relatively recent onset (symptomatic period 17 +/- 24 months) rheumatoid arthritis (RA) (experimental group; EG), and 20 age- and sex-matched healthy people (control group; CG). The comparison was repeated after a period of 6 months, when 16 patients had carried out progressive strength training. At baseline maximal grip strength and maximal dynamic unilateral strength of the knee extensors in the EG were significantly (P < 0.05) lower in comparison to the CG. The groups did not differ from each other in maximal isometric strength of the trunk flexors and extensors or the knee extensors. The 6-month dynamic strength training in the …
Effect of time-of-day-specific strength training on muscular hypertrophy in men.
2009
The purpose of the present study was to examine effects of time-of-day-specific strength training on muscle hypertrophy and maximal strength in men. A training group underwent a 10-week preparatory training (wk 0-wk 10) scheduled between 17:00 and 19:00 hours. Thereafter, the subjects were randomized either to a morning or afternoon training group. They continued with a 10-week time-of-day-specific training (wk 11-wk 20) with training times between 07:00 and 09:00 hours and 17:00 and 19:00 hours in the morning group and afternoon groups, respectively. A control group did not train but was tested at all occasions. Quadriceps femoris (QF) cross-sectional areas (CSA) and volume were obtained b…
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±…
Evolution of electromyographic signal, running economy, and perceived exertion during different prolonged exercises
2000
International audience; The purpose of this study was to compare the electromyographic (EMG) signal of the vastus lateralis muscle obtained during a run section of a triathlon and at the end of a prolonged run performed at the same running velocity. Seven subjects were studied on three occasions: a 2 h 15 min triathlon (30 min swimming, 60 min cycling, and 45 min treadmill running at 75% of the maximal aerobic speed), a 2 h 15 min run, where the last 45 min (Prolonged Run, PR) were run at the same speed as the Triathlon Run (TR) on a motorized treadmill, and a 45 min Isolated Run (IR) performed at the same TR and PR velocity. The three experimental trials were randomised. Oxygen uptake (VO …
Effect of explosive type strength training on isometric force- and relaxation-time, electromyographic and muscle fibre characteristics of leg extenso…
1985
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, …
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 …
Blood and urinary abnormalities induced during and after 24-hour continuous running: A case report
2016
In this reported clinical case, a healthy and well-trained male subject [aged 37 years, maximal oxygen uptake (V[Combining Dot Above]O2max) 64 mL·kg·min] ran for 23 hours and 35 minutes covering 160 km (6.7 km/h average running speed). The analysis of hematological and biochemical parameters 3 days before the event, just after termination of exercise, and after 24 and 48 hours of recovery revealed important changes on muscle and liver function, and hemolysis. The analysis of urine sediments showed an increment of red and white blood cells filtrations, compatible with transient nephritis. After 48 hours, most of these alterations were recovered. Physicians and health professionals who monito…
Androgen receptors and testosterone in men—Effects of protein ingestion, resistance exercise and fiber type
2007
The purpose of this study was to examine the impact of protein ingestion on circulating testosterone and muscle androgen receptor (AR) as well as on insulin-like growth factor-I (MGF and IGF-IEa) responses to a resistance exercise (RE) bout in (57-72 year) men. Protein (15 g whey) (n=9) or placebo (n=9) was consumed before and after a RE bout (5 sets of 10 repetition maximums), and vastus lateralis muscle biopsies were taken pre, 1 and 48 h post-RE. The protein ingestion blunted the RE-induced increase in serum free and total testosterone while the RE bout significantly increased muscle AR mRNA levels in older men (P<0.05). However, protein ingestion did not significantly affect AR mRNA or …