Effects of resistance training combined with ischemic preconditioning on muscle size and strength in resistance-trained individuals.

Abstract

The present study investigated the effects of resistance training combined with ischemic preconditioning (IPC) on muscle size and strength in resistance-trained men. Sixteen resistance-trained men were divided into two groups (Placebo and IPC) and trained twice a week for 6 weeks. Preconditioning protocols consisted of four, 5-min cycling bouts of ischemia/Placebo (250 or 10 mmHg, respectively) interspersed with 5 min of reperfusion (without pressure) alternated in each leg. Thirty minutes after the preconditioning protocol, participants performed 4 sets to concentric failure at 75% of one repetition-maximum (1-RM) in unilateral knee extension exercise. Muscle thickness (ultrasound) and 1RM were assessed at baseline and 72 hours after the last training session. ANCOVA was used to compare muscle thickness and 1RM changes, using muscle thickness and 1-RM baseline values, respectively, as covariates. Significance level was set at P<0.05. Average of number of repetitions was higher in IPC compared to Placebo (13±4 and 11±2, respectively; P=0.0002). Muscle thickness did not change in either group from pre- to post-6 weeks (P=0.32). IPC improved 1-RM more than Placebo (P=0.04). IPC may augment greater strength gains in resistance-trained men due to an increase in training volume.