Maximal oxygen uptake at the same fat‐free mass is greater in men than women

Abstract

Maximal oxygen uptake (VO(2max)) is commonly divided by body mass or fat-free mass (body mass minus fat mass) in order to make it size independent so that comparisons among persons of different size can be made. However, numerous studies have shown that the ratio created is not size-independent. Analysis of covariance (ANCOVA) allows a dependent variable to be compared between groups at a common value of a covariate. The purpose of this study was to compare VO(2max) at the same fat-free mass (FFM) in 230 sedentary subjects (half men) who ranged in age from 20 to 70 years. The subjects underwent maximal cardiopulmonary exercise testing on a cycle ergometer as ventilation and the expired gas fractions were being measured. Two ANCOVA models were evaluated. The dependent variable, fixed factor and covariate(s) in the linear model were VO(2max), sex and FFM, respectively. The corresponding terms in the log-linear model were ln VO(2max), sex, and ln FFM and age. Sex made a significant contribution to both models. In the linear model, the mean VO(2max) at the same FFM was 27% higher in men (2,444 versus 1,929 ml min(-1); P<0.001). In the log-linear model, the corresponding value at the same FFM and age was 32% higher in men (2,368 versus 1,794 ml min(-1); P<0.001). The goodness of fit indices of squared multiple correlation coefficient and standard error of estimate were significantly better for the log-linear model. We conclude that VO(2max) at the same FFM is considerably higher in men than in women who have a sedentary lifestyle.

Deep mineral water accelerates recovery after dehydrating aerobic exercise: a randomized, double-blind, placebo-controlled crossover study

“…Our participants were female physically active students, and their aerobic capacity may be considered higher because of the 10–15% difference between female and male untrained persons, as well as athletes, because of morphophysiological differences [26]. VO 2 max at the same fat-free mass is considerably (~30%) higher in sedentary men than in sedentary women [27]. Mild hypohydration exacerbates cardiovascular and thermoregulatory strain and tends to impair endurance performance, but greater aerobic fitness attenuates these physiological effects.…”

Longitudinal differences in aerobic capacity between children with sickle cell anemia and matched controls

“…Among the physiologic correlates of VO 2peak in healthy populations, fat free mass (FFM) is increasingly recognized as an important factor in both adults and children . FFM may influence aerobic capacity through augmentation of the skeletal muscle pump and venous return, and it has been suggested that FFM may account for observed sex differences in VO 2peak . Among children, the relationship between FFM and VO 2peak may be dependent on pubertal maturity, as both increase during adolescence .…”

The relevance of body composition assessment for the rating of perceived exertion in trained and untrained women and men

“…VO 2 and VO 2 max values are commonly reported per body mass, but less commonly per lean body mass, fat free mass, or skeletal muscle mass (SMM), in order to offset sex differences based on varying body composition between the sexes ( Lewis et al, 1986 ; Price et al, 2022 ). Nevertheless, men may still yield higher VO 2 max values of up to 27% based on fat free mass compared to women ( Davis et al, 2006 ). Since VO 2 resembles energy expenditure of about 20 kJ/l oxygen ( Brooks, 2012 ) and is connected to MPO through the factor of exercise efficiency ( Böning et al, 2017 ), evaluating MPO not only in absolute terms or per body mass (BM) ( Hettinger et al, 1961 ), but also per SMM would be of interest.…”