Rest periods between sets during an isokinetic peak torque testing protocol reported in literature range from 30 to 180s, and are very inconsistent. Furthermore, the optimal rest periods for older adults remains unclear.
This study assessed the minimal time for a between sets rest period during a common isokinetic knee extension strength-testing protocol of twenty older Brazilian men, aged 60 to 74 years.
The volunteers underwent unilateral knee extension (Biodex System 3) testing to determine their individual isokinetic peak torque at 60, 90, and 120°/s. The contraction speeds and the rest periods between sets (30, 60 and 90 s) were randomly performed in three different days with a minimum rest period of 48 hours. Significant differences between and within sets were analyzed using a One Way analysis of variance (ANOVA) with repeated measures. Statistical significance was accepted at an alpha level of p< 0.05.
Although, at angular velocity of 60°/s produced a higher peak torque, there were no significant differences in peak torque among any of the rest periods. Likewise, there were no significant differences between mean peak torque among all resting periods (30, 60 and 90s) at angular velocities of 90, and 120°/s.
The results showed that during a common isokinetic strength testing protocol a between set rest period of at least 30 s is sufficient for recovery before the next test set in older men.