Background: The purpose of the study was to examine the effects of training volume in bench press (BP) on acute mechanical, metabolic, and cardiovascular responses, and the time course of recovery. Methods: Fourteen men with moderate resistance training experience performed, in randomized order and separated by one week, three BP protocols differing in volume: 3 (LOW), 15 (MOD), and 24 (HIG) repetitions. To isolate the effect of training volume by minimizing fatigue accumulation across repetitions, short rest periods were inserted between repetitions. The rest duration was individualized based on the performance impairment induced in each repetition. A battery of tests was performed at baseline (Pre) and post-exercise, in the following order: (a) heart rate (HR), blood systolic and diastolic pressure (SBP and DBP), and oxygen saturation (SpO2), (b) blood lactate, and (c) dynamic strength test, which was also conducted at 24 h-Post and 48 h-Post. Results: Performance within-session (best, average, and last velocity, as well as velocity loss) was similar for all protocols. A significant “protocol × time” interaction was observed for SBP, although no significant differences between protocols were found. No significant differences were observed for DBP or SpO2. All protocols showed similar lactate concentrations at Post and similarly increased velocity at 60% 1RM load at 24 h-Post and 48 h-Post. Conclusions: individualizing inter-repetition rest periods based on velocity loss allows matching fatigue across different bench press volumes, which produced similar mechanical, metabolic, and cardiovascular responses, indicating that volume alone does not determine acute physiological load.
Páez-Maldonado et al. (Mon,) studied this question.