Menstrual and oral contraceptive cycle phases do not affect submaximal and maximal exercise responses.

Abstract

To examine whether the menstrual or monophasic oral contraceptive cycle phases affect submaximal (oxygen uptake ( O2 ) kinetics, maximal lactate steady-state (MLSS)) and maximal ( O2max , time-to-exhaustion (TTE)) responses to exercise in healthy, active women. During the mid-follicular or inactive-pill phase and the mid-luteal or active-pill phase of the respectivemenstrual or oral contraceptive cycle, 15 non-oral contraceptive users (meanandstandard deviation(SD) (±): 27±6 years; 171±5cm; 65±7kg) and 15 monophasic oral contraceptive users (24±4 years; 169±10cm; 68±10kg) performed: one O2 kinetics test; one ramp-incremental test; two to three 30-minute constant-load cycling trials to determine the power output corresponding to MLSS (MLSSp ), followed by a TTE trial. The phase of the menstrual or oral contraceptive cycle did not affect the time constant of the O2 kinetics response (τ O2 ) (mid-follicular, 20±5seconds and mid-luteal, 18±3seconds; inactive-pill, 22±8seconds and active-pill, 23±6seconds), O2max (mid-follicular, 3.06±0.32Lmin-1 and mid-luteal, 3.00±0.33Lmin-1 ; inactive-pill, 2.87±0.39Lmin-1 and active-pill, 2.87±0.45Lmin-1 ), MLSSp (mid-follicular, 181±30W and mid-luteal, 182±29W; inactive-pill, 155±26W and active-pill, 155±27W), and TTE (mid-follicular, 147±42seconds and mid-luteal, 128±54seconds; inactive-pill, 146±70seconds and active-pill, 139±77seconds) (P>.05). The rate of perceived exertion (RPE) at minute 30 of the MLSSp trials was greater in the mid-follicular phase (6.2±1.5) compared with the mid-luteal phase (5.3±1.4) for non-oral contraceptive users (P=.022). The hormonal fluctuations between the menstrual and oral contraceptive cycle phases had no detectable effects on submaximal and maximal exercise performance, even when RPE differed.