Fit for comparison: controlling for cardiorespiratory fitness in exercise physiology studies of sex as a biological variable.

ABSTRACT: More studies in exercise physiology are investigating sex as a biological variable, but the potential confounding effect of cardiorespiratory fitness is often neglected. As maximal oxygen uptake ( V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{max}}}}$ ) correlates with many physiological outcomes at rest and in response to exercise, differences in V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{max}}}}$ between male and female participants may hinder interpretation. Here we revisit decades-old arguments that advocate for matching males and females for V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{max}}}}$ normalized to fat-free mass (FFM) when investigating sex differences in the context of exercise. The rationale for using FFM to normalize V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{m

SUBMITTER: Tripp TR 

PROVIDER: S-EPMC12013801 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature