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  • McDougall Jiang posted an update 1 day, 11 hours ago

    Bodyweight training (BWT) is a style of interval exercise based on classic principles of physical education. Limited research, however, has examined the efficacy of BWT on cardiorespiratory fitness. This is especially true for simple BWT protocols that do not require extraordinarily high levels of effort. We examined the effect of a BWT protocol, modelled after the original “Five Basic Exercises” (5BX) plan, on peak oxygen uptake (VO2peak) in healthy, inactive adults (20 ± 1 y; body mass index 20 ± 5 kg/m2; mean ± SD). Participants were randomized to a training group that performed 18 sessions over six weeks (n=9), or a non-training control group (n = 10). The 11-minute session involved five exercises (burpees, high knees, split squat jumps, high knees, squat jumps), each performed for 60-seconds at a self-selected “challenging” pace, interspersed with active recovery periods (walking). Mean intensity during training was 82 ± 5% of maximal heart rate, rating of perceived exertion was 14 ± 3 out of 20, and compliance was 100%. ANCOVA revealed a significant difference between groups after the intervention, such that VO2peak was higher in the training group compared to control (34.2 ± 6.4 vs 30.3 ± 11.1 ml/kg/min; p = 0.03). selleck chemicals llc Peak power output during the VO2peak test was also higher after training compared to control (211 ± 43 vs 191 ±50 W, p = 0.004). There were no changes in leg muscular endurance, handgrip strength or vertical jump height in either group. We conclude that simple BWT- requiring minimal time commitment and no specialized equipment – can enhance cardiorespiratory fitness in inactive adults. These findings have relevance for individuals seeking practical, time-efficient approaches to exercise.Postural control is a major falls risk factor, therefore identifying protective mechanisms is essential. Physical activity enhances postural stability but effect duration has been minimally researched. The current study investigated if prolonged early life training exposure protected neuromuscular balance processes later in life. Static and dynamic balance variables were assessed in 77 healthy adults. Two age ranges (18 – 35yr, young; > 50yr, retired) were divided into weight bearing athlete and control groups; young athlete (YA), young control (YC), retired athlete (RA) and retired control (RC). Static balance was quantified using force platform derived sway velocity (mm.s-1) and C90area (mm2) data (stable and unstable surfaces, eyes open and closed) Dynamic balance was assessed using the Y balance test (YBT). Results demonstrated significant age effect across groups. However, an athletic effect was evident only assessing dynamic balance and static time to error variables. Mean time to error data (YA, 27.8 ± 5.8; YC, 20.5 ± 11.1; RA, 9.4 ± 8.5; RC, 8.6 ± 9.1 s) recorded significant age and athletic effects for the most challenging condition completed (single leg stance, eyes closed, stable surface). Mean maximum YBT composite score (YA, 90.0 ± 5.4%; YC, 83.6 ± 6.5%; RA, 80.8 ± 10.7%; RC, 72.4 ± 15.5%) demonstrated an age effect, and also identified a group effect in the retired cohorts. The current study supports research highlighting declined balance with ageing. Overall, former athleticism did not significantly enhance static balance in later life. Dynamic balance incorporates muscle strength possibly inferring a protective role in former athletes.This study aimed to investigate the effects of free leucine supplementation on muscle recovery from resistance exercise (RE) in young adults. Fourteen untrained subjects (23.9 ± 3.6 years old) underwent RE sessions (leg press and hack squat three sets of 8-12 reps at 70% 1RM) supplemented with leucine (LEU two daily doses of 3g) or a placebo (PLA), separated by a seven-day washout period. Following each occasion, participants were evaluated in three subsequent days (24h, 48h, and 72h) for muscle recovery via a repetition-to-failure test. The following markers were assessed repetition performance, perceived exertion, lactate, creatine kinase, muscle soreness (DOMS), testosterone, and cortisol. No significant difference was observed between LEU and PLA conditions (p > 0.05). Number of repetitions performed in the repetition-to-failure tests, perceived exertion, cortisol, and testosteronecortisol ratio did not change over time (p > 0.05). Creatine kinase increased immediately after exercise, at 24h, and 48h, and was attenuated at 72h post-exercise, while testosterone, lactate, and DOMS increased at 24h post-exercise (p less then 0.05) and remained elevated up to 72h. All outcomes were similar between LEU and PLA. Results indicate that a 6g daily dose of free leucine supplementation does not improve muscle recovery following lower-limb RE in untrained young adults.Caffeine improves short-to-moderate distance running performance, but the effect of caffeine on repeated sprints are equivocal. This research determined if caffeine improved exercise tolerance during repeated-sprint exercise. iCV is a running velocity that distinguishes intermittent running velocities (velocities ≤ iCV) that are sustainable from those resulting in a predictable time to exhaustion (velocities > iCV). Seven physically active men (age = 21.6 ± 1.5 years, body mass = 72.8 ± 5.1 kg, VO2max = 56.9 ± 9.8 mL/kg/min) ingested caffeine (5 mg/kg) or placebo (crossover design) 60 min prior to an intermittent critical velocity (iCV) test. The treadmill grade and velocity at VO2max (vVO2max) were used for iCV testing, and consisted of 3 bouts (10 sec running and 10 sec passive rest) at 130, 110 and 120% vVO2max. Each bout continued until volitional exhaustion and was separated by 20 min of passive rest. Total distance and duration were recorded to determine exercise tolerance using the iCV model. Caffeine ingestion increased running duration at 110% vVO2max (p = 0.02), but not at 120 (p = 0.93) and 130% vVO2max (p = 0.14). Caffeine did not improve iCV model parameters. A single dose of caffeine consumed 60 min before repeated-sprints can improve performance at 110% vVO2max, but not at higher velocities.