A Meta-Analysis of Studies Comparing Maximal Oxygen Uptake in Men and Women

Abstract

Since [Vdot]O₂ max (ml/minute · kg body weight) is known to be the primary determinant of work capacity in weight-bearing exercise, the quantification of sex-specific factors influencing aerobic capacity is necessary if appropriate work capacity and endurance performance expectations and standards are to be developed for men and women. Yet, due to varying procedures and sample characteristics, large discrepancies exist among studies concerning the magnitude of the sex difference in [Vdot]O₂ max. The purpose of this article is to provide an integrative review of the research comparing [Vdot]O₂ max in men and women using the meta-analytic strategy proposed by Glass (1976). An overall estimate of the magnitude of the sex effect for each of three expressions of [Vdot]O₂ max is provided. When removing the variability in aerobic capacity due to body size and body fatness, the magnitude of difference in [Vdot]O₂ max between men and women is substantially reduced. When expressed relative to fat-free weight, the [Vdot]O₂ max values of the males are, on the average, 12 to 15% higher than those of the females. Sex-specific differences in relative hemoglobin content may be responsible for a part of this remaining difference. However, a substantial portion of the sex difference in [Vdot]O₂ max (ml/minute · kg fat-free weight) is probably attributable to gender-associated differences in level of physical activity/conditioning. The ability to clearly identify the sex-related components of aerobic capacity is an objective warranting further investigation.