Acute effect of stretching performed before a resistance exercise session using different intervals on maximum repetitions performance in recreationally trained adults

Abstract

The present study proposed to compare the acute effect of stretching (SE) before resistance exercise (RE) sessions using different intervals (30 vs. 60 vs. 120 seconds) on maximal repetition performance of recreationally trained adults. Twenty men (age: 29.5 ± 7.05 years; height: 82.92 ± 8.47 kg; weight: 1.78 ± 0.07 cm; body mass index: 26.03 ± 1.55 m2kg-1) recreationally trained in RE (≥ 6 months) completed 4 interventions: 1) RE with 60-second intervals (RE60"), 2) SE plus RE with 30-second intervals (SE+RE30"), 3) SE plus RE with 60-second intervals (SE+RE60"), and 4) SE plus RE with 120-second intervals (SE+RE120"). The RE consisted of three sets until muscle failure of the following exercises: bench press, bench press 35°, decline bench press, biceps curl, and biceps curl 45° at 80% of 10RM. The SE involved two sets of 30-second static SE for chest and biceps separated by a 40-second passive interval. The maximum number of repetitions performed until muscle failure was counted at the end of each set. The results of this study show a progressive reduction in maximum repetitions performance between sets and exercises in tested protocols with and without SE. Significant reductions were presented for the SE+RE30" protocol compared to the RE60" and SE+RE120" protocols. The present study suggests that 60" intervals between sets are necessary to avoid a significant reduction in maximum repetitions performance. Keywords: Neuromuscular performance, strength, strength training