Effects of bench step exercise on arterial stiffness in post-menopausal women: contribution of IGF-1 bioactivity and nitric oxide production.

OBJECTIVE

To examine the effect of bench step exercise on arterial pulse wave velocity (PWV) and the associated contribution of insulin-like growth factor (IGF)-1 bioactivity and nitric oxide (NO).

DESIGN

Twenty-six elderly (post-menopausal) women were randomly allocated to a bench step exercise group or a control group. The participants in the bench step exercise group practiced a 12-week home-based bench step exercise for 10-20min, 3 times daily (i.e., for a total of 140min/week at the intensity level of lactate threshold (LT)). In addition to conventional risk factors of atherosclerosis, PWV, IGF-1/IGF binding protein (IGFBP)-3 molar ratio (an index for IGF-1 bioactivity), and urinary nitrite/nitrate (NO(x)) excretion were measured before and after the intervention.

RESULTS

BMI, systolic blood pressure, fasting plasma glucose, low-density lipoprotein cholesterol, LT, and PWV were significantly improved in the bench step exercise group. A significant positive correlation between changes in PWV and IGF-1/IGFBP-3 molar ratio, and a significant negative correlation between changes in IGF-1/IGFBP-3 molar ratio and urinary NO(x) excretion were found in the bench step exercise group.

CONCLUSION

The bench step exercise leads to improvements in not only the classical risk factors of atherosclerosis but also the arterial stiffness in elderly women, partly through NO production via IGF-1 bioactivity.