First-Repetition Mechanical Performance Retention During Repeated Bench Press Following Standard- and Cambered-Bar Warm-Ups

Background: Exercise-specific warm-up may influence fatigue-related performance decline and the restoration of performance between repeated resistance-training sets. This study examined whether a cambered-bar warm-up, compared with a standard-bar warm-up, affected first-repetition velocity and power retention and acceleration–time characteristics. Methods: This randomized parallel-group study included twenty resistance-trained men randomly allocated to a cambered-bar condition (CAM; n = 10) or a standard-bar condition (ST; n = 10). The warm-up comprised four sets at 30%, 50%, 60%, and 70% of one-repetition estimated maximum (1RM). After 10 min, participants completed four sets of five standard-bar repetitions at 75% of 1RM, with 2 min inter-set recovery. First-repetition mean concentric velocity retention was the principal outcome. First-repetition power retention, acceleration index, range of motion (ROM), peak velocity, time to peak velocity, and inter-set velocity rebound were analyzed using linear mixed-effects models. Results: During the loading protocol, first-repetition mean concentric velocity and power retention were greater in CAM than ST by 9.82 and 11.65 percentage points, respectively (exact participant-level permutation p = 0.044 and p = 0.012, respectively). No condition × target-set interactions were observed, indicating overall between-condition differences averaged across L2–L4 rather than different set-to-set trajectories. No condition effect was observed for inter-set velocity rebound. CAM increased warm-up ROM by 6.34 cm compared with ST. No condition effects or condition × stage interactions were observed for warm-up acceleration index, peak velocity, or time to peak velocity. The acceleration index increased across loading sets independently of condition. Conclusions: A cambered-bar warm-up increased movement range and was associated with greater retention of first-repetition mean concentric velocity and power during repeated bench press sets. However, no evidence was found for a between-condition difference in immediate inter-set velocity rebound. These findings suggest that the cambered-bar warm-up condition may support the maintenance of first-repetition mechanical performance across repeated sets, although confirmation in larger randomized crossover studies is required.