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The barbell squat is a multijoint exercise often employed by athletes and fitness enthusiasts due to its beneficial effects on functional and morphological neuromuscular adaptations. This study compared the effects of squat variations on lower limb muscle strength and hypertrophy adaptations. Twenty‐four recreationally trained females were assigned to a 12‐week front squat (FS; n = 12) or back squat (BS; n = 12) resistance training protocol (twice per week). Maximum dynamic strength (1‐RM) on the 45° leg press, a nonspecific strength test, and muscle thickness of the proximal, middle, and distal portions of the lateral thigh were assessed at baseline and post‐training. A significant time versus group interaction was observed for 1‐RM values (F(1,22) = 10.53; p = 0.0004), indicating that BS training elicits greater improvements in muscle strength compared with FS training (p = 0.048). No time versus group interactions were found for muscle thickness (F(1,22) = 0.103; p = 0.752); however, there was a significant main effect of time for the proximal (F(1,22) = 7.794; p = 0.011), middle (F(1,22) = 7.091; p = 0.014), and distal portions (F(1,22) = 7.220; p = 0.013) of the lateral thigh. There were no between‐group differences for any muscle thickness portion (proximal: p = 0.971; middle: p = 0.844; and distal: p = 0.510). Our findings suggest that BS elicits greater improvements in lower limb muscle strength on the 45° leg press than FS, but hypertrophic adaptations are similar regardless of variations during the squat exercise. Highlights: Back squat training elicited greater strength‐related improvements in a nonspecific strength test than front squat training.Hypertrophic adaptations of the lateral thigh are similar between both squat variations.Both squat variations elicited similar growth at proximal, middle, and distal regions of the lateral thigh. [ABSTRACT FROM AUTHOR]

The effects of acute caffeine supplementation on muscular strength remain unclear. We examined the effects of two different doses of caffeine on muscle strength and calcium in plasma compared to placebo using a crossover, randomized, double-blind, placebo-controlled design. Twenty-one (n = 21) recreationally resistance-trained participants were randomly assigned into three experimental conditions: 6 mg·kg bw−1 of caffeine (CF6); 8 mg·kg bw−1 of caffeine (CF8); or placebo (PLA), with a 7-day washout period between conditions. Muscular strength assessments were made for both upper (bench press) and lower body muscles (squat and deadlift). Calcium release in plasma was measured on five different occasions. Bench press (CF8: 100.1 ± 1.9 kg; PLA: 94.2 ± 2.5 kg), deadlift (CF8: 132.8 ± 3.5 kg; PLA: 120.7 ± 5.7 kg), and squat (CF8: 130.1 ± 4.9 kg; PLA 119.4 ± 5.4 kg) strength were all significantly (p < 0.001) improved in CF8 compared to PLA. Calcium release in plasma was significantly increased in CF8, whereas no changes were observed in CF6 or PLA. Overall, 8 mg·kg bw−1 of caffeine appears to be an effective dose to optimize upper and lower body muscular strength and calcium release in recreationally trained participants. [ABSTRACT FROM AUTHOR]

Aging is associated with reductions in muscle and bone mass and brain function, which may be counteracted by several lifestyle factors, of which exercise appears to be most beneficial. However, less than 20% of older adults (> 55 years of age) adhere to performing the recommended amount of resistance training (≥ 2 days/week) and less than 12% regularly meet the aerobic exercise guidelines (≥ 150 min/week of moderate to vigorous intensity aerobic exercise) required to achieve significant health benefits. Therefore, from a healthy aging and clinical perspective, it is important to determine whether other lifestyle interventions (independent of exercise) can have beneficial effects on aging muscle quality and quantity, bone strength, and brain function. Creatine, a nitrogen containing organic compound found in all cells of the body, has the potential to have favorable effects on muscle, bone, and brain health (independent of exercise) in older adults. The purpose of this narrative review is to examine and summarize the small body of research investigating the effects of creatine supplementation alone on measures of muscle mass and performance, bone mineral and strength, and indices of brain health in older adults. [ABSTRACT FROM AUTHOR]

Background: To determine the effects of a low dose, short-term Creatine monohydrate (Cr) supplementation (0.03 g.kg.d−1 during 14 d) on muscle power output in elite youth soccer players. Methods: Using a two-group matched, double blind, placebo-controlled design, nineteen male soccer players (mean age = 17.0 ± 0.5 years) were randomly assigned to either Cr (N = 9) or placebo (N = 10) group. Before and after supplementation, participants performed a 30s Wingate Anaerobic Test (WAnT) to assess peak power output (PPO), mean power output (MPO), fatigue index (FI), and total work. Results: There were significant increases in both PPO and MPO after the Cr supplementation period (P ≤ 0.05) but not the placebo period. There were also significant increases in total work, but not FI, after the Cr supplementation and placebo periods (P ≤ 0.05). Notably, there were differences in total work between the Cr and placebo groups after (P ≤ 0.05) but not before the 14 d supplementation period. Conclusion: There is substantial evidence to indicate that a low-dose, short-term oral Cr supplementation beneficially affected muscle power output in elite youth soccer players. [ABSTRACT FROM AUTHOR]

Background: To determine the effects of a low dose, short-term Creatine monohydrate (Cr) supplementation (0. 03 g.kg.d-1 during 14 d) on muscle power output in elite youth soccer players. Methods: Using a two-group matched, double blind, placebo-controlled design, nineteen male soccer players (mean age = 17.0 ± 0.5 years) were randomly assigned to either Cr (N = 9) or placebo (N = 10) group. Before and after supplementation, participants performed a 30s Wingate Anaerobic Test (WAnT) to assess peak power output (PPO), mean power output (MPO), fatigue index (FI), and total work. Results: There were significant increases in both PPO and MPO after the Cr supplementation period (P ≤ 0.05) but not the placebo period. There were also significant increases in total work, but not FI, after the Cr supplementation and placebo periods (P ≤ 0.05). Notably, there were differences in total work between the Cr and placebo groups after (P ≤ 0.05) but not before the 14 d supplementation period. Conclusion: There is substantial evidence to indicate that a low-dose, short-term oral Cr supplementation beneficially affected muscle power output in elite youth soccer players. [ABSTRACT FROM AUTHOR]