Comparação da hipertrofia muscular regional no reto abdominal entre os exercícios "supra" e "infra 30º"

Abstract

The aim of this study was to compare the variation in cross-sectional area (CSA) of the rectus abdominis (RA) regions after 9 weeks of training using different exercise protocols, namely infra-30° abdominal and supra-abdominal exercises. Thirty-six resistance-trained female volunteers were divided into a control group and 2 experimental groups. The volunteers in the experimental groups performed 3 weekly training protocols consisting of 2-4 sets of 10 repetitions at 100% of 10RM and a final set in which the volunteer should perform the maximum number of repetitions, repetition duration of 4s (2s concentric and 2s eccentric muscle action) and 180s rest. The infra group performed the infra-30° abdominal exercise, while the supra group performed the supra-abdominal exercise. The control group did not perform any specific exercise for the RA in the same period, moreover, all 3 groups continued to perform the other resistance training exercises as usual. Before and after the training, all volunteers underwent ultrasound exams to determine the CSA of the RA muscle in its four bellies. The pre-post variation of the CSA of the muscle bellies was analyzed using a two-way analysis of variance (group*belly) with repeated measures and the significance level adopted was 0.05. The results indicated that the experimental groups showed significant increases in CSA compared to the control group (p<0.05). However, the experimental groups were not significantly different from each other and did not have a regionally different response. Thus, it can be concluded that the manipulation of the exercise does not generate regionally different hypertrophy responses in the RA.