Acute Vascular Responses to Moderate Intensity Continuous Training Across the Natural Menstrual Cycle and Oral-Contraceptive Cycle in Healthy Young Premenopausal Women

We have previously reported the acute vascular responses to a single bout of high intensity interval training (HIIT) across the natural menstrual cycle (MC) and oral-contraceptive cycle (OC) in healthy young premenopausal women. Here, we investigated in twenty-one healthy young premenopausal women whether the acute vascular responses to a single bout of moderate intensity continuous training (MICT) differ: 1) among the early-follicular, late-follicular, and mid-luteal phases of the MC (n=11); 2) between the active (estradiol and progestin) and placebo phases of the OC (n=10); and 3) compared to the acute vascular responses to HIIT across the MC (n=11) and OC (n=10). The order of MICT and HIIT was randomized. Acute vascular responses to a single bout of MICT and HIIT were assessed before exercise, at the end of exercise, and during recovery. Carotid-femoral pulse wave velocity (cfPWV) and augmentation index at heart rate 75 bpm (AIx@75)—indices of arterial stiffness and wave reflection, respectively—and central blood pressure were assessed using SphygmoCor XCEL. We found that the acute vascular (i.e., central systolic and diastolic blood pressure, cfPWV, and AIx@75) responses to MICT were not significantly different among the early-follicular, late-follicular, and mid-luteal phases of the MC ( P ≥0.1; phase x time) and between the active and placebo OC phases ( P ≥0.4; phase x time). When comparing the acute vascular responses to MICT vs. HIIT, we found that central systolic and diastolic blood pressure, cfPWV, and AIx@75 did not change differently in response to MICT vs. HIIT across the MC ( P ≥0.2; exercise type x phase x time) and OC ( P ≥0.5; exercise type x phase x time). In conclusion, we have demonstrated in healthy young premenopausal women that the acute arterial stiffness, wave reflection, and central blood pressure responses to MICT: 1) are not influenced by hormonal fluctuations among the early-follicular, late-follicular, and mid-luteal MC phases; 2) are not influenced by hormonal differences between the active and placebo OC phases; and 3) are not different compared to the acute vascular responses to HIIT across the MC and OC. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.