Day-to-day variation in operating lung volumes and the role of menstrual cycle phases

Authors

Emma Winstead, James Madison UniversityFollow

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

Date of Graduation

5-15-2025

Semester of Graduation

Spring

Degree Name

Master of Science (MS)

Department

Department of Kinesiology

First Advisor

Stephanie Kurti-Luden

Second Advisor

Nicholas Luden

Third Advisor

Michael Saunders

Abstract

The purpose of this study was to evaluate day-to-day variability in operating lung volumes (OLV)—specifically end-expiratory lung volume (EELV) and end-inspiratory lung volume (EILV)—between males and females, as well as the occurrence of expiratory flow limitation (EFL) during exercise. An exploratory aim was to assess whether menstrual cycle phase influences these respiratory variables in females. Although these measures are ubiquitous in exercise and pulmonary laboratories, very little is known about their day-to-day variability. Twenty-four healthy subjects (12 F, 12 M) participated in exercise testing on three separate days with at least 48 hours between tests. Each visit was comprised of a battery of pulmonary function tests that were completed before and after an incremental test to exhaustion to assess maximal oxygen uptake (VO2peak). Female subjects completed a Menstrual Phase Identification Questionnaire (MPIQ) to assess whether they were in the luteal or follicular phase at the beginning of each visit. Intraclass correlation coefficients (ICCs) were calculated to assess the day-to-day reliability of all pulmonary function and metabolic variables measured at rest and during exercise. Women exhibited more variability in OLV compared to men. The menstrual cycle may have influenced this outcome, as increased variability was present in the luteal phase compared to the follicular phase. Women see more variability in OLV than men which may be due to the impact of the menstrual cycle and the increases in progesterone seen in the luteal phase.