Effects of rest interval during high-repitition resistance training on strength, aerobic fitness and repeated-sprint ability

The effect of altering the rest period on adaptations to high-repetition resistance training is not well known. Eighteen activefemales were matched according to leg strength and repeated-sprint ability and randomly allocated to one of two groups.One group performed resistance training with 20-s rest intervals between sets, while the other group employed 80-s restintervals between sets. Both groups performed the same total training volume and load. Each group trained 3 days a week for5 weeks [15- to 20-repetition maximum (RM), 2 – 5 sets]. Repeated-sprint ability (566-s maximal cycle sprints), 3-RM legpress strength, and anthropometry were determined before and after each training programme. There was a greaterimprovement in repeated-sprint ability after training with 20-s rest intervals (12.5%) than after training with 80-s restintervals (5.4%) (P¼0.030). In contrast, there were greater improvements in strength after training with 80-s rest intervals(45.9%) than after training with 20-s rest intervals (19.6%) (P¼0.010). There were no changes in anthropometry for eithergroup following training. These results suggest that when training volume and load are matched, despite a smaller increase instrength, 5 weeks of training with short rest periods results in greater improvements in repeated-sprint ability than the sametraining with long rest periods.