Sex and light physical activity impact popliteal, but not brachial artery flow-mediated dilation in physically active young adults

Applied Physiology, Nutrition, and Metabolism, Ahead of Print. When controlling for baseline diameter, males have greater brachial flow-mediated dilation (BA-FMD) responses than females. It is unclear whether sex differences in baseline diameter also influences popliteal FMD (POP-FMD), which may be impacted by cardiorespiratory fitness and physical activity levels. We hypothesized that males would exhibit greater BA-FMD and POP-FMD when allometrically scaled to baseline diameter. FMD (ultrasonography), cardiorespiratory fitness (indirect calorimetry), and objectively measured physical activity were assessed in males (n = 13; age, 23 ± 3 years; peak oxygen consumption, 48.0 ± 7.1 mL·kg−1·min−1) and females (n = 13; age, 24 ± 2 years; peak oxygen consumption, 36.8 ± 6.0 mL·kg−1·min−1). Both groups had similarly high levels of moderate-to-vigorous intensity physical activity (503 ± 174 vs. 430 ± 142 mi n·week−1, p = 0.25). However, males were more aerobically fit (p< 0.001) and females accumulated more light-intensity physical activity (182 ± 67 vs. 127 ± 53 min·week−1, p = 0.03). Relative and allometrically scaled BA-FMD were similar (both, p ≥ 0.09) between sexes. In contrast, relative (6.2% ± 1.0% vs. 4.6% ± 1.4%, p = 0.001) and scaled (6.8% ± 1.7% vs. 4.7% ± 1.7%, p = 0.03) POP-FMD were greater in fe males. Relative POP-FMD was related to light-intensity physical activity in the pooled sample (r = 0.43; p =...
Source: Applied Physiology, Nutrition, and Metabolism - Category: Physiology Authors: Source Type: research