Effects of Resistance Training Techniques on Metabolic Responses in Trained Males.

This study investigated the effects of biset, drop-set and traditional resistance training (RT) techniques on metabolic responses in resistance-trained males. Fifteen trained males (age 29.7 ± 6.1 years; body mass 83.4 ± 7.6 kg; RT experience 11.4 ± 6.7 years; one-repetition maximum (1RM) barbell bench press: body mass ratio 1.4 ± 0.1 a.u.) were assigned to three experimental conditions, in a randomized crossover design. The experimental conditions were bi-set (3×10 repetitions at 70%1RM in barbell bench press followed by 10 repetitions at 60%1RM in incline bench press), drop-set (3×10 repetitions at 70%1RM followed by 10 repetitions at 50%1RM in barbell bench press) and traditional RT (3×20 at 60%1RM in barbell bench press). A portable gas analyzer was used to assess energy expenditure and maximal oxygen uptake during the experimental protocols. Blood lactate levels were assessed at baseline and 1, 3, and 5 minutes after the training session. There were no differences for total training volume (p = 0.999). Post hoc comparisons revealed that bi-set elicited higher aerobic energy expenditure (p = 0.003 vs. drop-set; p < 0.001 vs. traditional RT) and aerobic oxygen consumption (p = 0.034 vs. drop-set; p < 0.001 vs. traditional RT) than other RT schemes. There were no differences regarding anaerobic EE between-conditions (p > 0.05). There was a main effect of time and condition for blood lactate levels (p < 0.001). Post hoc comparisons revealed that drop-set training elicited higher blood lactate levels than traditional RT (p = 0.009). The results suggest that RT techniques may have a potential role in optimizing metabolic responses in resistance-trained males.

High Doses of Caffeine Increase Muscle Strength and Calcium Release in the Plasma of Recreationally Trained Men.

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.

Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints.

ABSTRACT: Zandona, BA, Ramos, RA, de Oliveira, CdS, McAnulty, SR, Ferreira, LHB, Smolarek, AC, Enes, AAN, Urbinati, KMdSS, Aragon, AA, Schoenfeld, BJ, and de Souza Junior, TP. Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints. J Strength Cond Res 36(6): 1636-1642, 2022-Beta-alanine (BA) supplementation has been shown to be effective in improving physical performance by increasing carnosine concentration. However, it is still necessary to know the effect of a maintenance dose on performance. Thus, this study aimed to investigate the effects of a maintenance dose of BA supplementation on performance. Forty-four anaerobically trained men with 23.9 ± 3.8 years of age, 176.0 ± 0.05 cm height, 81.2 ± 7.5 kg body mass, and 15.5 ± 2.9% of body fat performed a cycle ergometer test consisting of 4 sprints of 30 s with 4 minutes of active recovery. The study comprised 3 phases: (a) presupplementation, (b) supplementation with 6.4 g·d-1 BA or placebo, and (c) postsupplementation with a maintenance dose of 1.2 g·d-1 of BA or interruption of supplementation. Data were analyzed using generalized estimated equations with a priori 0.05 level of significance. The placebo group and interruption group presented a lower power (7.28 ± 0.66 and 7.71 ± 0.42 W·kg-1 vs. 8.04 ± 0.84 and 9.25 ± 1.18 W·kg-1, respectively; p < 0.05) during the third sprint in postsupplementation, whereas the maintenance group maintained the required power (7.47 ± 1.03 vs. 8.74 ± 1.07 W·kg-1; p > 0.05). The placebo group also presented higher percentage of fatigue (44.5% ± 12.3 and 44.8% ± 7.7 vs. 37.6 ± 7.2%; p = 0.021) and higher subjective perception of exertion (8.92 ± 0.90 vs. 8.00 ± 1.60; p = 0.028). Therefore, the maintenance dose of 1.2 g·d-1 BA was effective in maintaining performance, whereas a reduction in performance was observed after supplementation interruption.

Effects of Creatine Supplementation on Properties of Muscle, Bone, and Brain Function in Older Adults: A Narrative Review.

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.

High doses of sodium bicarbonate increase lactate levels and delay exhaustion in a cycling performance test.

OBJECTIVES: It is well established that ingestion of sodium bicarbonate (NaHCO3) causes metabolic alkalosis. However, there is no consensus in terms of optimal NaHCO3 doses leading to enhanced performance. This study aimed to determine the effects of different NaHCO3 doses on performance and lactate clearance in non-professional cyclists. METHODS: Twenty-one cyclists performed the following three double-blind trials: 1) ingestion of 0.3 g · kg-1 body weight (BW) of placebo; 2) ingestion of 0.1 g · kg-1 BW NaHCO3 plus 0.2 g · kg-1 BW placebo (0.1 BC); and 3) ingestion of 0.3 g · kg-1 BW NaHCO3 (0.3 BC). Performance was evaluated after warm-up on the bike followed by a performance test until exhaustion. Lactate levels were monitored in blood samples before and immediately after performance tests. RESULTS: Lactate levels in the blood were significantly higher after exercise in 0.3 BC and 0.1 BC (15.12 ± 0.92 versus 10.3 ± 1.22 and 13.24 ± 0.87 versus 10.3 ± 1.22 mmol/L; P < 0.05) compared with control. Significant improvements in performance were only identified in 0.3 BC group (76.42 ± 2.14; P = 0.01). CONCLUSIONS: The present study found that 0.3 g · kg-1 BW NaHCO3 is effective in improving performance and improving blood lactate levels in cyclists compared with control and 0.1 g · kg-1 BW NaHCO3.

Effect of low dose, short-term creatine supplementation on muscle power output in elite youth soccer players.

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.