Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCA174

Poster Communications

Endothelial function in healthy postmenopausal women: effects of chronic and acute exercise

J. Craig1, R. Ferguson1, E. O'Donnell1

1. School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom.

Aerobic exercise training is associated with decreased cardiovascular disease risk, including attenuation of the age-associated decline in endothelial function. However, growing evidence suggests that this vascular benefit may be obviated in post-menopausal women (PMW). To examine this further, we compared endothelial function in habitually exercise trained and untrained PMW, both before and after an acute bout of exercise. Two groups of healthy, age-matched (56.5±1 years) PMW were studied: habitually exercise trained PMW (≧2 hours moderate-to-vigorous intensity exercise/week for ≧5 years;TrPMW; n=6) and untrained PMW (no regular exercise for ≧5 years; (UntrPMW; n=7). Resting and peak calf blood flow (CBF), an index of endothelial function, were assessed using strain-gauge plethysmography. Vascular resistance (VR; mean arterial pressure/blood flow) was calculated. Serum measures of 17 beta-estradiol, sex-hormone binding globulin (SHBG) and testosterone were determined. Vascular measures were assessed before and 60 minutes after an acute bout of dynamic exercise (45 minutes walking at 60% VO2peak). Baseline: Groups did not differ (p>0.05; one-way ANOVA) in height (163.4±1.5 cm; overall mean±SEM), weight (61.7±2.3 kg), heart rate (60±2 beats/min), systolic blood pressure (BP; 118.6±3.1 mmHg), and serum measures of testosterone (0.9±0.1 nmol/L), SHBG (55.5±5.8 nmol/L), and 17 beta-estradiol (72.8±1.3 pmol/L). Resting and peak CBFand VR were also similar (p>0.05) between groups (Table 1). In contrast, VO2peak was higher (36.8±3.4 vs. 28.3±1.4 ml/kg/min; p<0.05), and BMI (21.5±1.2 vs. 24.4±1.0 kg/m2) and resting diastolic BP (73.6±1.0 vs. 78.8±1.8 mmHg) lower (p<0.05) in the TrPMW versus UntrPMW. Post-exercise: Using repeated measures ANOVA (group x condition), within-group measures of CBF (Table 1), heart rate, and systolic and diastolic BP were increased (p<0.05) and VR decreased (p<0.05) in both groups. In contrast, no between-group differences (p>0.05) were detected. Our preliminary findings demonstrate that resting and peak peripheral blood flow and VR do not differ between habitually trained and untrained PMW. A single bout of dynamic exercise similarly increased blood flow and decreased VR in both groups. These observations suggest that while a single bout of dynamic exercise acutely improves endothelial function, chronic aerobic exercise training does not attenuate the age-associated decline in endothelial function in healthy PMW.

Where applicable, experiments conform with Society ethical requirements