Effects of a Heart Rate–Based Rest Strategy During Resistance Exercise on Training Volume, Blood Lactate, and Muscle Soreness

This study compared heart rate responses, actual rest duration, training volume, blood lactate, and muscle soreness between a heart rate–based rest method (HRBR) and a time-based rest method (TBR) during resistance exercise. Twelve healthy young men completed five sets of the bench press at 75% 1RM under both conditions using a randomized crossover design. Heart rate was consistently higher in the TBR condition, whereas rest duration was longer in the HRBR condition and increased across sets. Training volume was greater in the HRBR condition during the fifth set but decreased across sets in both conditions. Blood lactate did not differ between rest methods and increased up to the second set. Muscle soreness was significantly higher in the TBR condition at 48 and 72 h post-exercise. These findings indicate that HRBR may be effective for maintaining training volume, albeit with reduced time efficiency, whereas TBR may induce greater metabolic stress and muscle soreness.