Additional analyses for aerobic fitness when additionally adjusted for change in body mass index or change in pubertal stage. Values at baseline and follow-up are unadjusted means (SD).

*Differences in average change and 95% confidence intervals (CI) are the differences between intervention (INT) and controls (CON) after adjustment by mixed-model regression analysis for grade, gender, baseline value of the outcome and cluster (class). ICC = intracluster correlation coefficient; dferr = error degrees of freedom. Z-scores are based on internal references.