Effect of different types of resistance exercise on arterial compliance and calf blood flow.

Low-intensity blood flow restricted (LI-BFR) resistance training has been shown to produce comparable increases in muscle hypertrophy to traditional high-intensity (HI) resistance training. However, a comparison of the acute vascular responses between the two types of exercise has not been made. The purpose of this study is to compare the acute vascular responses of HI, low-intensity (LI), and LI-BFR resistance exercise. Using a randomized, cross-over design, 11 young (28 ± 5 years) males completed three acute resistance exercise bouts (HI, LI and LI-BFR). Before (Pre), and starting at 15- and 45-min after each exercise bout, large (LAEI) and small (SAEI) artery compliance and calf blood flow were assessed. Calf blood flow was normalized per unit pressure as calf vascular conductance (CVC). Repeated measures (condition × time) ANOVA revealed a main time effect for LAEI and a main condition effect for SAEI. LAEI increased following exercise but returned to baseline at 45-min post. SAEI was greater during the HI condition compared to the LI or LI-BFR conditions. There was a significant condition × time interaction for CVC. CVC was elevated at 15- and 45-min post during the HI condition and at 15-min following the LI condition. CVC was not altered following the LI-BFR condition. These results suggest that HI, LI, and LI-BFR resistance exercise cause similar acute increases in large artery compliance but HI causes greater increases in small artery compliance and calf vascular conductance than LI or LI-BFR resistance exercise.