Prediction of VO2max with daily step counts for Japanese adult women

The purpose of the study was to develop a new non-exercise VO2max prediction model using a physical activity (PA) variable determined by pedometer-determined step counts (SC, steps day(-1)) in Japanese women aged 20-69 years old. Eighty-seven and 102 subjects were used to develop the prediction model, and to validate the new model, respectively. VO2max was measured using a maximal incremental test on a bicycle ergometer. SC was significantly related to VO2max (partial correlation coefficient r = 0.40, P < 0.001) after adjusting for BMI (kg m(-2)) and age (years). When the new prediction equation developed by multiple regression to estimate VO2max from age, BMI, and SC (R = 0.71, SEE = 5.3 ml kg(-1) min(-1), P < 0.001) was applied to the Validation group, predicted VO2max correlated well with measured VO2max (r = 0.81, P < 0.001), suggesting that SC is a useful PA variable for non-exercise prediction of VO2max in Japanese women.