Acute effects of equated volume-load resistance training leading to muscular failure versus non-failure on neuromuscular performance

Background/objective: The aim of this study was to compare the acute effects of resistance training to failure (TF) and non-failure (TNF) with volume-load equalization on neuromuscular performance in recreationally resistance-trained adults. Methods: Twenty-two trained men (age 21.4 +/- 2.3 years) were included in a controlled, randomized, and design cross-over investigation with two experimental conditions and one-week of washout interval between them. The participants performed parallel back-squat adopting TF or TNF with volume, in- tensity, and rest between sets equalized. Countermovement jump (CMJ) height and peak power (PP) were used as mechanical indicators of neuromuscular performance. The mechanical variables were assessed in five moments (pre-experiment, post 15-s, 10-min, 20-min, and 30-min). Results: When compared with the TNF condition, TF presented greater decrement on CMJ height (P < 0.001) and PP (P 0.001) performance. The CMJ height and PP performance in parallel back-squat exercise following the TNF condition returned to the pre-experiment values 10-min after (P 0.05). On the other hand, the TF condition promoted greater decrement in CMJ and PP performance compared with the pre-experiment and TNF protocol even 20-30 min later (P < 0.05). Conclusion: These findings suggest that TF promotes greater acute impairment on neuromuscular per- formance even when volume-load is equalized.