A Maximal Cycle Test with Good Validity and High Repeatability in Adults of All Ages

In 11680 individuals (18-85 years) maximal oxygen consumption (VO(2)max) was estimated indirectly in a maximal cycle test using a prediction model developed in a young population (15-28 years). A subsample of 182 individuals (23-77 years) underwent 2 maximal cycle tests with VO(2)max estimated indirectly in both tests and measured directly in one test. Agreement between the direct measurement and the indirect estimate of VO(2)max and repeatability of the indirect estimates of VO(2)max were examined by Bland-Altman plots, limits of agreement (LOA) and coefficient of repeatability (CR). The indirect method (mean VO(2)max=3132mlmin(-1)) underestimated VO(2)max as compared to the direct method (mean VO(2)max=3190mlmin(-1)) in men (bias: 58mlmin(-1) (95% LOA-450 and 565)) and overestimated VO(2)max in women (mean VO(2)max=2328 vs. 2258mlmin(-1), bias: -70mlmin(-1) (95% LOA-468 and 328)). The mean difference between the 2 indirect estimates was non-significant (men: -11.9mlmin(-1), women: 18.3mlmin(-1)) with a CR of 279mlmin(-1) (8.9%) in men and 274mlmin(-1) (11.7%) in women. The validity of the indirect method was good despite minor sex-specific bias. Owing to this bias we suggest a new prediction model of VO(2)max. The maximal cycle test was highly repeatable.