Effects of a repetition-based rest adjustment strategy on superset training performance and fatigue

This study aimed to validate the feasibility of a repetition-based method for adjusting inter-set rest intervals during superset resistance training (RT). Twenty young adults completed three protocols—fixed (3-min rest), self-selected (participant-determined rest), and repetition-based (rest adjusted by prior repetition count)—in randomized order, performing five agonist–antagonist supersets (bench press and bench pull) at 75% 1RM. Results indicated greater repetition volume in later supersets for the self-selected and repetition-based protocols compared to the fixed protocol (F = 2.1, p = 0.037, ωp 2 = 0.056). However, blood lactate concentrations were significantly higher in the repetition-based protocol compared to both the self-selected and fixed protocols (F = 7.3, p = 0.002, ωp 2 = 0.252). No differences among protocols were found in fastest set velocity or perceived exertion (F = 0.3–2.8, p = 0.077–0.782). Regarding time efficiency, the fixed protocol was most efficient, followed by the repetition-based, with the self-selected protocol being least efficient. These findings indicate that the repetition-based approach offers an effective complementary strategy to traditional fixed and self-selected rest methods, especially in contexts emphasizing mechanical performance and session efficiency.