The aim of this study was to compare the acute influence of two intensities of aerobic characteristic on the number of repetitions in a strength training (ST) session in physically active older women. Eight women (67.5 ± 4.8 years; 58.6 ± 2.2 kg; 156 ± 5.9 cm) with experience in both activities, volunteered to perform the aerobic activity in both intensities (60 or 80% HRmax.), followed by a training session on leg-press, leg extension and leg curl exercises, at different days. In order to determine the maximal load, 10RM test and re-test were conducted for the selected exercises, and the HRmax. was calculated through the Balke-Ware maximal test protocol. The number of repetitions in each set after aerobic intensity training was analyzed using one-way ANOVA, followed by Scheffé post-hoc test. The total number of repetitions in each exercise and sequence was analyzed by the t-Student test for dependent samples. The results showed significant reductions in the total number of repetitions for all training sessions (sum of all repetitions in all exercises), as well as in the number of repetitions per exercise, after aerobic training intensities of 80 and 60%. We have also verified that after 80% of HRmax. after aerobic exercise, all evaluated subjects showed higher degree of fatigue, expressed by their perceived exertion. Fatigue became more evident when we applied an inter-sequential analysis, which showed a higher reduction in strength training performance when 80% of HRmax was applied. We conclude that, regardless the training intensity, 20 minutes of aerobic training may be enough to produce a negative impact on strength training performance of physically active elderly women.
strength training; resistive exercises; performance; concurrent training
