Purpose
The purpose of the study was to examine if the modified Chester step test (CST2) provides a more accurate prediction of maximal oxygen uptake ( \(\dot{V}O_{2\max }\) ) when compared against the traditional test (CST1).
Methods
Fifty healthy participants completed the CST1, the CST2, and a treadmill-based \(\dot{V}O_{2\max }\) test. Tests were conducted in a randomised order, at the same time of day, in similar environmental conditions, with at least 24 h rest between trials. Systematic measurement bias across all three trials (CST1, CST2, and \(\dot{V}O_{2\max }\) ) was examined using a repeated measures ANOVA. Method comparison and validity of the CST1 and CST2 predicted \(\dot{V}O_{2\max }\) were further examined using the 95% limits of agreement [95% LoA = bias ± 1.96 × standard deviation of the differences (SDdiff)].
Results
Mean ± SD of the CST1 and CST2 predicted \(\dot{V}O_{2\max }\) , and actual \(\dot{V}O_{2\max }\) were 42.9 ± 7.9, 42.9 ± 7.6, and 41.8 ± 7.4 ml.kg−1.min−1, respectively. No significant bias was shown between the CST1 and CST2 predicted \(\dot{V}O_{2\max }\) and actual \(\dot{V}O_{2\max }\) (P > 0.05). The 95% LoA between the CST1 predicted \(\dot{V}O_{2\max }\) and actual \(\dot{V}O_{2\max }\) and the CST2 predicted \(\dot{V}O_{2\max }\) and actual \(\dot{V}O_{2\max }\) were similar (1.04 ± 10.7 ml.kg−1.min−1 and 1.08 ± 11 ml.kg−1.min−1, respectively), translating to 28% and 29% prediction error in the worst case.
Conclusions
Despite claims that the collection of additional heart rate (HR) data during the CST2 provides a more accurate prediction of \(\dot{V}O_{2\max }\) , the current study observed no difference between the CST1 or CST2 prediction of \(\dot{V}O_{2\max }\) . Provided the same version is used during repeated trials, either test can be used to provide an estimation of \(\dot{V}O_{2\max }\) .
