Impact of Menstrual Cycle on Submaximal Exercise VO2 and Critical Power in Active Eumenorrheic Females

Authors

Emma W. Ware, Texas Woman's UniversityFollow
Adelle Kanaan, Texas Woman's UniversityFollow
Erika R. Zoellner, Texas Woman's UniversityFollow
Catherine Mbango, Texas Woman's UniversityFollow
Deltra Muoki, Texas Woman's UniversityFollow
Wayne Brewer, Texas Woman's UniversityFollow
Mindy Patterson, Texas Woman's UniversityFollow
Derek Miketinas, Texas Woman's UniversityFollow
Siddhartha Angadi FACSM, University of VirginiaFollow
Brandon J. Sawyer, Point Loma Nazarene UniversityFollow
Glenn A. Gaesser FACSM, Arizona State UniversityFollow
Wesley J. Tucker, Texas Woman's UniversityFollow

Abstract

The effects of the menstrual cycle (MC) on exercise metabolism and performance are equivocal. PURPOSE: To investigate whether the MC impacted submaximal exercise oxygen consumption (VO₂) and Critical Power (CP) in recreationally active, eumenorrheic females. METHODS: Eight eumenorrheic females (Age: 33±8 y, VO_2max: 36.9±3.8 ml/kg/min) completed fasted exercise testing in 3 distinct phases of the MC (early follicular, late follicular, and mid luteal). MC phase was determined using calendar-based counting, ovulation test strips, and confirmed via serum hormones (estrogen and progesterone). For submaximal exercise, participants cycled for 20 min at 50% VO_2max while VO₂ and respiratory exchange ratio (RER) were measured with indirect calorimetry. Rating of perceived exertion (RPE) was measured with Borg 6-20 Scale. After submaximal exercise, participants rested for 10 min and performed a 3-min all-out test to assess CP. Power output (W) was continuously measured to determine CP, which was defined as mean W in final 30 sec of 3-min all-out test. Repeated measures ANOVA was used to assess differences in submaximal responses for VO₂ and RER, and 3-min all-out CP. Friedman tests were used to assess differences in RPE. RESULTS: For submaximal cycling, VO₂ did not differ across MC (early follicular: 1.27±0.22 L/min, late follicular: 1.27±0.20 L/min, mid-luteal: 1.27±0.22 L/min; p-value=0.98; effect size=0.01). However, RER was higher during late follicular (0.91±0.03) than early follicular (0.89±0.05) and mid-luteal (0.89±0.03) phases (p=0.12; effect size=0.30). RPE was lower during late follicular (11±2) compared to early follicular (13±2) and mid luteal (13±2)(p=0.04). For the 3-min all-out test, CP did not differ by MC phase (early follicular: 138±31 W, late follicular: 136±33 W, mid luteal: 136±31 W; p=0.52; effect size=0.07). CONCLUSIONS: These preliminary results in 8 recreationally active, eumenorrheic females suggest that submaximal exercise VO₂ and CP do not differ across the MC, despite minor differences in submaximal substrate utilization and perceived exertion.

Recommended Citation

Ware, Emma W.; Kanaan, Adelle; Zoellner, Erika R.; Mbango, Catherine; Muoki, Deltra; Brewer, Wayne; Patterson, Mindy; Miketinas, Derek; Angadi, Siddhartha FACSM; Sawyer, Brandon J.; Gaesser, Glenn A. FACSM; and Tucker, Wesley J. (2024) "Impact of Menstrual Cycle on Submaximal Exercise VO2 and Critical Power in Active Eumenorrheic Females," International Journal of Exercise Science: Conference Proceedings: Vol. 2: Iss. 16, Article 136.
Available at: https://digitalcommons.wku.edu/ijesab/vol2/iss16/136