Eight weeks of resistance training with blood flow restriction improve cardiac function and vascular endothelial function in healthy young Asian males.

Background: Resistance training with blood flow restriction (BFR) is a physiological ischaemic training method. Before it is applied to patients with coronary artery disease, it must be proven safe and effective.
Methods: Twenty-four healthy adult males were randomly assigned to three groups: the resistance training (RT) group, low-pressure BFR and resistance training (LP-RT) group and high-pressure BFR and resistance training (HP-RT) group. The training protocol was 20 times/min/set, with a 2-min break, five sets/day and 5 d/week for 8 weeks. Cardiac function, haemodynamics and vascular endothelial function were evaluated before and after the first training and the last training.
Results: There were no significant differences among groups before and after training. After 8 weeks of training, the resting heart rate (p<0.05) of the three groups significantly decreased (p<0.05). The rate-pressure product in the LP-RT group significantly decreased (p<0.05) compared with before training. Just after the last training, heart rate (p<0.05) and cardiac output (p<0.05) in the LP-RT and HP-RT groups significantly decreased compared with those just after the first training. At the end of the experiment, vascular endothelial growth factor (VEGF; p<0.01), soluble VEGF receptor (VEGFR) (p<0.05) and interleukin-6 (p<0.01) significantly increased, except for soluble VEGFR in the RT group.
Conclusions: Low-intensity resistance training with BFR moderately alters cardiac function. The expression levels of proteins related to vascular endothelial function have significantly changed. Both findings suggest that low-intensity resistance training with BFR may be safely and effectively applied to patients with coronary artery disease.
(© The Author(s) 2020. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)