The aim of this study was to compare the acute response of sustainability of repetitions and the volume of resistance exercise sessions conducted with different intensities, in trained older women. The study included 16 older women (68.3 ± 6.0 years, 69.8 ± 10.6 kg, 157.6 ± 6.5 cm). After the determination of load related to 15 maximum repetitions (RM) in the leg press, two experimental sessions (48-72 hours apart) were conducted by performing one of two different intensities (90% or 100% of 15 RM). Crossover balanced design was used to determine the sessions order. The session with 100% of 15 RM involved the performance of three sets until muscle fatigue, while the session with 90% of 15 RM was performed in two sets with 15 repetitions and a last one until muscle fatigue. The rest interval between sets was 120 seconds. The training volume obtained with 90% of 15 RM was 22.5% higher (P < 0.01) than that volume obtained with the 100% of 15 RM. The sustainability of repetitions the exercise carried out at 100% of 15 RM was compromised in two final series of the session (P <0.01), with differences in the protocol carried out with less intensity. The analysis of results suggests that reduction of 10% in the load corresponding to 15 RM presents a significant effect on the sustainability of number of repetitions between sets and training volume when compared to exercise performed at 100% of 15 RM in trained older women.
aging; muscle fatigue; muscle strength; resistance exercise
