Original Article Sex-Specific Equations to Estimate Maximum Oxygen Uptake in Cycle Ergometry

Background: Aerobic fitness, assessed by measuring VO2max in maximum cardiopulmonary exercise testing (CPX) or by estimating VO2max through the use of equations in exercise testing, is a predictor of mortality. However, the error resulting from this estimate in a given individual can be high, affecting clinical decisions. Objective: To determine the error of estimate of VO2max in cycle ergometry in a population attending clinical exercise testing laboratories, and to propose sex-specific equations to minimize that error. Methods: This study assessed 1715 adults (18 to 91 years, 68 % men) undertaking maximum CPX in a lower limbs cycle ergometer (LLCE) with ramp protocol. The percentage error (E%) between measured VO2max and that estimated from the modified ACSM equation (Lang et al. MSSE, 1992) was calculated. Then, estimation equations were developed: 1) for all the population tested (C-GENERAL); and 2) separately by sex (C-MEN and C-WOMEN). Results: Measured VO2max was higher in men than in WOMEN:-29.4 ± 10.5 and 24.2 ± 9.2 mL.(kg.min)-1 (p < 0.01)