Even low physical activity levels improve vascular function in overweight and obese postmenopausal women.

OBJECTIVE: Some individuals with cardiovascular risk are unable to achieve even the lower internationally recommended level of physical activity (PA). We aimed to study the impact of a lower-than-advised level of PA on small artery vascular function and oxidative stress in overweight and obese postmenopausal women. METHODS: Forty-seven overweight and obese postmenopausal women completed a 4-month program of 1-hour low-intensity PA for 2 days per week. Before and after the intervention, PA level (metabolic equivalent tasks/h/wk), endogenous antioxidant status (superoxide dismutase and erythrocyte lysate and glutathione peroxidase erythrocyte lysate concentrations, superoxide dismutase plasma and glutathione peroxidase plasma [GPXa] activities, and oxidized low-density lipoprotein), asymmetrical dimethylarginine concentrations, endothelial function by small artery reactive hyperemia index (saRHI), and resting heart rate (RHR) were assessed. RESULTS: After the intervention, a significant increase in GPXa and decreases in asymmetrical dimethylarginine concentrations and RHR (P < 0.001 for all) were observed. Increases in PA were positively associated with increases in saRHI (r = 0.330, P = 0.027) and GPXa (r = 0.299, P = 0.05) and a decrease in RHR (r = -0.297, P = 0.047). Multivariate analyses showed that the independent predictors of saRHI improvement were an increase in PA (ß = 2.63; 95% CI, 1.24-4.19; P = 0.019), a decrease in RHR (ß = 1.96; 95% CI, 1.01-5.03; P = 0.048), and an increase in GPXa (ß = 2.64; 95% CI, 1.18-5.08; P = 0.021). CONCLUSIONS: Even low-intensity PA improves antioxidant capacity, RHR, and saRHI in postmenopausal women. Advising postmenopausal women to increase their PA at any level seems warranted based on our preliminary and hypothesis-generating data.

High-density lipoprotein cholesterol and apolipoprotein A1 levels strongly influence the reactivity of small peripheral arteries.

OBJECTIVE: Reactive hyperaemia after shear stress is a surrogate marker of endothelial function. However, the mechanisms controlling the dilation capacity of small peripheral resistance arteries are not well characterised. We evaluated reactive hyperaemia by peripheral artery tonometry (PAT) in the acral arteries and studied their clinical and biochemical determinants. METHODS: Eight hundred sixteen subjects at intermediate to high cardiovascular risk were recruited. The reactive hyperaemia index (RHI) of small digital arteries was measured by PAT. Clinical history data, anthropometry and biochemical parameters were also analysed. We studied the associations between clinical and biochemical factors and small artery RHI. RESULTS: HDL cholesterol and apolipoprotein A1 levels were strongly and directly correlated with an increased dilation response. Metabolic syndrome components, such as increased waist circumference, hypertriglyceridaemia and smoking, were inversely associated with RHI as were serum markers of inflammation. The predictors of small peripheral artery RHI were HDL cholesterol, which had a protective effect, and smoking, which had a negative impact. CONCLUSION: HDL cholesterol and apolipoprotein A1 levels had a strong, positive correlation with small artery reactive hyperaemia, whereas smoking, waist circumference and triglyceride levels were inversely associated. HDL cholesterol was the main determinant of RHI in small peripheral resistance arteries.