Exercise V˙e and physical performance at altitude are not affected by menstrual cycle phase

Abstract

We hypothesized that progesterone-mediated ventilatory stimulation during the midluteal phase of the menstrual cycle would increase exercise minute ventilation (V˙e; l/min) at sea level (SL) and with acute altitude (AA) exposure but would only increase arterial O2 saturation ([Formula: see text], %) with AA exposure. We further hypothesized that an increased exercise[Formula: see text] with AA exposure would enhance O2 transport and improve both peak O2 uptake (V˙o 2 peak; ml ⋅ kg−1 ⋅ min−1) and submaximal exercise time to exhaustion (Exh; min) in the midluteal phase. Eight female lowlanders [33 ± 3 (mean ± SD) yr, 58 ± 6 kg] completed aV˙o 2 peak and Exh test at 70% of their altitude-specificV˙o 2 peak at SL and with AA exposure to 4,300 m in a hypobaric chamber (446 mmHg) in their early follicular and midluteal phases. Progesterone levels increased ( P < 0.05) ∼20-fold from the early follicular to midluteal phase at SL and AA. PeakV˙e (101 ± 17) and submaximalV˙e (55 ± 9) were not affected by cycle phase or altitude. Submaximal[Formula: see text] did not differ between cycle phases at SL, but it was 3% higher during the midluteal phase with AA exposure. NeitherV˙o 2 peak nor Exh time was affected by cycle phase at SL or AA. We conclude that, despite significantly increased progesterone levels in the midluteal phase, exercise V˙e is not increased at SL or AA. Moreover, neither maximal nor submaximal exercise performance is affected by menstrual cycle phase at SL or AA.