Introduction: The study evaluated the role of life-long physical activity for leg vascular function in post-menopausal women (61±1 years).

Method: The study design was cross-sectional with 3 different groups based on their self-reported physical activity level with regard to intensity and volume over the past decade: inactive (n=14), moderately active (n=12), and very active (n=15). Endothelial dependent and smooth muscle dependent leg vascular function were assessed by ultrasound doppler measurements of the femoral artery during infusion of acetylcholine, the nitric oxide (NO) donor sodium nitroprusside and the prostacyclin analog epoprostenol. Thigh muscle biopsies and venous plasma samples were obtained for assessment of vasodilator systems.

Results: The very active group was found to have 76% greater responsiveness to acetylcholine compared to the sedentary group accompanied by 200% higher prostacyclin synthesis during ach infusion. Smooth muscle cell responsiveness to sodium nitroprusside and epoprostenol was not different between groups. The protein amount of endothelial nitric oxide synthase and endogenous antioxidant enzymes in muscle tissue was higher in the very active than the inactive group. The moderately active group had a similar endothelial and smooth muscle cell responsiveness as the inactive group. A secondary comparison with a smaller group (n=5) of habitually active young (24±2 yrs) women indicated that smooth muscle cell responsiveness and endothelial responsiveness is affected by age per se.

Conclusion: This study shows that leg vascular function and the potential to form prostacyclin and NO in late post-menopausal women, is influenced by the extent of life-long physical activity.