The Effects of Individualized Low- and Moderate-Load Circuit Training on Physical Performance, Hormonal Responses, And Hematological Adaptations in Resistance-Trained Men.

This study aimed to compare the effects of low-load circuit training (LL-CT) and moderate-load circuit training (ML-CT) on physical performance adaptations, hormonal responses, and hematological parameters in resistance-trained men. Thirty-two resistance-trained males (age 20.31 ± 1.00 y) were randomly assigned to three groups: LL-CT (n = 11), ML-CT (n = 11), or CON (n = 10). Participants in the training groups performed two sessions per week for 8 weeks. Both protocols consisted of four rounds of five exercises in a circuit format with a 30 s work:30 s rest duty cycle and 2-min inter-set rest. Exercise intensity was prescribed as 30% 1RM (LL-CT) or 70% 1RM (ML-CT), where 1RM was determined for four lifts: power clean, back squat, bench press, and deadlift. Loads during each exercise were expressed as a percentage of that exercise's own 1RM. Pre- and post-intervention measures included one-repetition maximum in the back squat and bench press (kg); countermovement jump and squat jump height (cm); 30-m sprint time (s); 505 change-of-direction time (s); peak power (W) and relative peak power (W·kg