Reliability of the velocity achieved during the last repetition of sets to failure and its association with the velocity of the 1-repetition maximum

BACKGROUND: This study aimed to determine the reliability of the velocity achieved during the last repetition of sets to failure (V(last)) and the association of V(last) with the velocity of the 1-repetition maximum (V(1RM)) during the paused and touch-and-go bench press (BP) exercises performed in a Smith machine. METHODS: A total of 96 healthy men participated in this study that consisted of two testing sessions. A single BP variant (paused BP or touch-and-go BP) was evaluated on each session in a randomized order. Each session consisted of an incremental loading test until reaching the 1RM, followed by two sets of repetitions to failure against a load ranging from 75% to 90% of 1RM. RESULTS: The reliability of V(last) was unacceptable for both BP variants (CV > 18.3%, ICC < 0.60). The correlations between V(1RM) and V(last) were small for the paused BP (r = 0.18) and moderate for the touch-and-go BP (r = 0.37). CONCLUSIONS: Although these results suggest that V(last) could be a better indicator of the minimal velocity threshold than V(1RM), the low reliability of V(last) and the similar values of V(last) for both BP variants suggest that a standard V(1RM) should be used to estimate the 1RM from the individualized load-velocity relationship.