The Effect of Circuit Resistance Training on Plasma Concentration of Endothelin-1, Nitric Oxide and Vascular Diameter in Elderly Men

Background: aging is associated with an increase in vascular dysfunction but it can be prevented by exercise training. However, the effect of circuit resistance training as a useful training method in improving cardio-respiratory and muscular strength is unclear. Objectives: The aim of this study was to investigate the effect of CRT on plasma endothelin-1, nitric oxide (NO) and vascular size in aged men. Methods: Twenty healthy agedmen(555 year) were randomly divided into control and CRT groups. CRT group performed circuit resistance training with 40 - 60 one repetitionmaximumfor twelve weeks (3 times per week). Vascular size, plasma endothelin-1 and NO, blood pressure and heart rate were measured forty eight hours before and after the training period. Results: CRTincreased the vascular sizeanddecreased endothelin-1andsystolic blood pressurecomparedto the pre-test; however, it hadnoeffectonNOconcentrationandheart rate. In comparison with the controlgroup, CRTsignificantly increased the vascular size and decreased endothelin-1 and blood pressure but there was no significant difference in NO concentration and heart rate between the two groups. Conclusions: Circuit resistance training as a proper training method could induce the increase in endothelial function in aged individual and prevents vascular dysfunction related to aging.