Introduction: Circuit resistance training is widely used to enhance physical performance. However, the acute-performance- and fatigue-related effects of exercise order and volume in circuit training, particularly between upper and lower limbs, remain unclear. Objectives: This study examined acute velocity-based responses to different exercise orders and volumes during full-body circuit resistance training. Methods: Thirty resistance-trained adults completed four circuit protocols: alternating exercises with maximal repetitions per exercise (A1), grouped exercises with maximal repetitions per exercise (G1), alternating exercises with 50% of maximal repetitions in the first round (A2), and grouped exercises with 50% of maximal repetitions in the first round (G2). Mean propulsive velocity (MPV) in the bench press and squat at 60% 1RM was assessed before and after each circuit. Results: A significant main effect of Time was observed for both bench press and squat MPV (p < 0.001), with no Intervention × Time interactions. Alternating configurations showed larger effect sizes, indicating greater velocity loss. Under equal volume, upper limbs exhibited greater performance decline than lower limbs. Conclusions: Although exercise order did not result in statistically significant differences, alternating configurations induced a greater magnitude of fatigue-related performance decline than grouped configurations, particularly in upper-body exercises.
Hermosilla-Perona et al. (Fri,) studied this question.