The Effects of Low-Load Resistance Training Combined with Blood Flow Restriction or Hypoxia on Cardiovascular Response: A Randomized Controlled Trial

Abstract

Low-load resistance training combined with vascular occlusion or hypoxia can increase muscle cross-sectional area (CSA), but the effect of such training on hormonal response and cardiovascular response is less clear. Thirty female netball athletes took part in a 5-week training of knee muscles in which low-load resistance exercise (20% 1-RM) was combined with either an occlusion pressure (KT, n = 10), hypoxic air (HT, n = 10), or no additional stimulus (CT, n = 10). Growth hormones (GHs), cardiovascular parameters, and CSA were measured before and after the training program. Compared to CT, both HT and KT showed a substantial increase in GH release after the first training bout (pre). After 5 weeks of training (post), the release of GH was substantially reduced in all groups. Compared to CT, HT showed a substantial decrease in SP (11.7 ± 11.3%, mean ± 90% CL) over the training period. The reduction in systolic blood pressure (SP) after hypoxic training resulted in a substantial decrease in the rate-pressure product (RPP) by 15.6 ± 9.6%, compared to CT. CSA from HT and KT is likely related to the heightened release of GH found after training. The hypoxic training protocol has a greater cardiovascular benefit than similar resistance training with blood flow restriction.