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Hill, MW, Roberts, M, Price, MJ, and Kay, AD. Effects of flywheel training with eccentric overload on standing balance, mobility, physical function, muscle thickness, and muscle quality in older adults. J Strength Cond Res 36(11): 3190-3199, 2022-This study investigated the effects of a 6-week eccentric overload flywheel training program on vastus lateralis (VL) and gastrocnemius medialis (GM) muscle thickness and muscle quality (echo intensity), mobility (Timed Up and Go [TUG]), physical function (sit-to-stand), and balance (postural sway) performance. Nineteen subjects were assigned to either a flywheel training group ( n = 11, age = 66.4 ± 5.2 years) or a control group ( n = 8, age = 65.9 ± 3.8 years). The flywheel group underwent twice weekly squat and calf raise exercises for 6 weeks with outcome measures assessed before and after training or a time-matched control period. Throughout the training, subjects were instructed to contract as fast as possible with maximal effort during the concentric phase and to maximally resist the pull during the eccentric phase. The alpha value was a priori set at p0.05. Statistically significant ( p0.05) mean ( SD ) increases in right and left VL (7.6-9.6 ± 7.7-9.8%) and GM (8.6-8.7 ± 6.4-11.5%) muscle thickness and a reduction in VL (10.2-11.3 ± 5.9-7.9%) and GM (11.7-11.9 ± 5.6-9.6%) echo intensity were accompanied by faster TUG time (13.7 ± 7.0%) improved sit-to-stand performance (17.8-23.5 ± 7.6 - 13.4%) and reduced postural sway (29.7-42.3 ± 13.2-24.2%) after 6 weeks of flywheel training. There were no differences in any outcome measures between the treatment and control group at baseline ( p0.05). Overall, we observed substantial gains in muscle thickness and muscle quality, in addition to enhanced physical function, balance, and mobility performance among older adults after flywheel training, which may have important implications for preserving the functional capacity of older adults.

Nevin, JP, Smith, P, Waldron, M, Patterson, S, Price, M, Hunt, A, and Blagrove, R. Efficacy of an 8-week concurrent strength and endurance training program on hand cycling performance. J Strength Cond Res 32(7): 1861-1868, 2018-The aim of this study was to investigate the effects of an 8-week concurrent strength and endurance training program in comparison with endurance training only on several key determinants of hand cycling performance. Five H4 and 5 H3 classified hand cyclists with at least 1 year's hand cycling training history consented to participate in the study. Subjects underwent a battery of tests to establish body mass, body composition, V[Combining Dot Above]O2peak, maximum aerobic power, gross mechanical efficiency (GME), maximal upper-body strength, and 30-km time-trial performance. Subjects were matched into pairs based on 30-km time-trial performance and randomly allocated to either a concurrent strength and endurance or endurance training only, intervention group. After an 8-week training program based on a conjugated block periodization model, subjects completed a second battery of tests. A mixed model, 2-way analysis of variance revealed no significant changes between groups. However, the calculation of effect sizes (ESs) revealed that both groups demonstrated a positive improvement in most physiological and performance measures with subjects in the concurrent group demonstrating a greater magnitude of improvement in body composition (ES -0.80 vs. -0.22), maximal aerobic power (ES 0.97 vs. 0.28), GME (ES 0.87 vs. 0.63), bench press 1 repetition maximum (1RM) (ES 0.53 vs. 0.33), seated row 1RM (ES 1.42 vs. 0.43), and 30-km time-trial performance (ES -0.66 vs. -0.30). In comparison with endurance training only, an 8-week concurrent training intervention based on a conjugated block periodization model seems to be a more effective training regime for improving the performance capabilities of hand cyclists.

This study examined the acute effects of NaHCO3 ingestion on repetitions to failure and rating of perceived exertion in the back squat and bench press in trained men. Eight resistance-trained men took part in this double-blind, randomized crossover experimental study whereby they ingested NaHCO3 (0.3 g·kg(-1) body mass) or placebo (sodium chloride NaCl: 0.045 g·kg(-1) body mass) solution 60 minutes before completing a bout of resistance exercise (3 sets of bench press and back squat exercise to failure at an intensity of 80% 1 repetition maximum). Experimental conditions were separated by at least 48 hours. Participants completed more repetitions to failure in the back squat after NaHCO3 ingestion (p = 0.04) but not for bench press (p = 0.679). Mean ± SD of total repetitions was 31.3 ± 15.3 and 24.6 ± 16.2 for back squat and 28.7 ± 12.2 and 26.7 ± 10.2 for bench press in NaHCO3 and placebo conditions, respectively. Repetitions to failure decreased as set increased for the back squat and bench press (p = 0.001, both). Rating of perceived exertion significantly increased with set for the back squat and bench press (p = 0.002, both). There was no significant change in blood lactate across time or between conditions. There were however treatment × time interactions for blood pH (p = 0.014) and blood HCO3 concentration (p = 0.001). After ingestion, blood pH and HCO3 (p = 0.008) concentrations were greater for the NaHCO3 condition compared with the placebo condition (p < 0.001). The results of this study suggest that sodium bicarbonate ingestion can enhance resistance exercise performance using a repetition to failure protocol in the first exercise in a resistance exercise session.

The purpose of this study was to determine the effects of sodium bicarbonate (NaHCO3) ingestion on intermittent running and subsequent performance. Eight healthy men volunteered to take part in the study. One hour after the ingestion of either NaHCO(3) or placebo (sodium chloride; NaCl) participants undertook 20 x 24-second runs on a motorized treadmill at the velocity eliciting maximal oxygen uptake (100% v-VO(2)max). After sprint 20 participants performed a run to volitional exhaustion at 120% v-VO(2)max. Capillary blood samples for blood pH, bicarbonate ([HCO(3)]), and lactate ([Bla]) concentration were taken pre and postingestion, every fifth sprint and after the performance run. After ingestion of NaHCO(3), blood [HCO(3)] increased from resting values (p0.05), and the increase in pH approached significance. Blood [HCO(3)(-)] continually decreased throughout intermittent exercise (p0.05) and decreased further after performance in both trials (p0.05). [Bla] was similar in both trials throughout intermittent exercise but was greater at exhaustion for NaHCO(3) (main effect for trial; p0.05). There was no significant difference in performance of the group between trials (78 +/- 22 and 75 +/- 22 seconds for NaHCO(3) and NaCl, respectively). The intercept of the relationships between [Bla] and [HCO(3)(-)] and between [Bla] and pH was greater during NaHCO(3) (p0.05), whereas the relationship between pH and [HCO(3)(-)] was unchanged (p0.05). The results of this study suggest that the ingestion of NaHCO(3) before intermittent type exercise was sufficient to induce metabolic alkalosis but did not significantly affect performance. However, because significant individual variations in performance were observed, an individual approach to bicarbonate ingestion is recommended based on the intensity and duration of the required performance.