RESUMO
The aim of this study was to compare 2 models of resistance training (RT) programs, nonperiodized (NP) training and daily nonlinear periodized (DNLP) training, on strength, power, and flexibility in untrained adolescents. Thirty-eight untrained male adolescents were randomly assigned to 1 of 3 groups: a control group, NP RT program, and DNLP program. The subjects were tested pretraining and after 4, 8, and 12 weeks for 1 repetition maximum (1RM) resistances in the bench press and 45° leg press, sit and reach test, countermovement vertical jump (CMVJ), and standing long jump (SLJ). Both training groups performed the same sequence of exercises 3 times a week for a total of 36 sessions. The NP RT consisted of 3 sets of 10-12RM throughout the training period. The DNLP training consisted of 3 sets using different training intensities for each of the 3 training sessions per week. The total volume of the training programs was not significantly different. Both the NP and DNLP groups exhibited a significant increase in the 1RM for the bench press and 45° leg press posttraining compared with that pretraining, but there were no significant differences between groups (p ≤ 0.05). The DNLP group's 1RM changes showed greater percentage improvements and effect sizes. Training intensity for the bench press and 45° leg press did not significantly change during the training. In the CMVJ and SLJ tests, NP and DNLP training showed no significant change. The DNLP group showed a significant increase in the sit and reach test after 8 and 12 weeks of training compared with pretraining; this did not occur with NP training. In summary, in untrained adolescents during a 12-week training period, a DNLP program can be used to elicit similar and possible superior maximal strength and flexibility gains compared with an NP multiset training model.
Assuntos
Força Muscular , Amplitude de Movimento Articular , Treinamento Resistido/métodos , Adolescente , Humanos , Masculino , Levantamento de PesoRESUMO
The purpose of the present study was to verify the acute effect of sodium bicarbonate supplementation on symptoms of gastrointestinal discomfort, acid-base balance and intermittent isometric handgrip test performance in Jiu-Jitsu athletes. Ten male (22.2 ± 3.9 years; 174 ± 0.07 cm; 74.5 ± 8.9 kg) jiu-jitsu athletes participated in this counterbalanced double-blind crossover study. Two protocols, a) supplementation with 0.3 g.kg-1 of body weight of sodium bicarbonate, and b) supplementation with 0.045 g.kg-1 of body weight of placebo substance, were employed. Gastrointestinal tolerability was assessed by the questionnaire. Blood samples were collected at three time points (baseline, pre-ISO, and post-ISO) to determine the responses of potential hydrogenionic (pH), bicarbonate (HCO3- ), base excess (EB) and lactate concentrations. The maximum voluntary contraction test and the intermittent isometric contraction test were also performed. As a result, none of the athletes reported significant gastrointestinal discomfort (p > 0.05). HCO3- , pH, and EB at the pre-ISO and post-ISO moments were significantly higher for the sodium bicarbonate protocol. Lactate concentrations were significantly higher for both post-ISO protocols (p = 0.000). There was no significant difference in the performance of the maximum voluntary contraction test and the intermittent isometric contraction test (p > 0.05). Thus, we conclude that sodium bicarbonate supplementation does not generate adverse responses resulting in gastrointestinal discomfort, and does not benefit performance yet promotes a state of metabolic alkalosis.