Appropriate scaling approach for evaluating peak VO(2) development in Southern Chinese 8 to 16 years old

OBJECTIVE: To investigate scaling approaches for evaluating the development of peak VO(2) and improving the identification of low cardiopulmonary fitness in Southern Chinese children and adolescents. METHODS: Nine hundred and twenty Chinese children and adolescents (8 to 16 years) underwent graded cardiopulmonary exercise test on a treadmill until volitional exhaustion. Peak VO(2) was corrected for the effects of body mass by ratio or allometric scaling. Z score equations for predicting peak VO(2) were developed. Correlations between scaled peak VO(2), z scores, body size and age were tested to examine the effectiveness of the approach. RESULTS: Eight hundred and fifty-two participants (48% male) were included in the analyses. Absolute peak VO(2) significantly increased with age in both sexes (both P<0.05), while ratio-scaled peak VO(2) increased only in males (P<0.05). Allometrically scaled peak VO(2) increased from 11 years in both sexes, plateauing by 12 years in girls and continuing to rise until 15 years in boys. Allometically scaled peak VO(2) was not correlated with body mass, but remained correlated with height and age in all but the older girls. Peak VO(2) z score was not correlated with body mass, height or age. CONCLUSIONS: Absolute and allometric scaled peak VO(2) values are provided for Hong Kong Chinese children and adolescents by age and sex. Peak VO(2) z scores improve the evaluation of cardiopulmonary fitness, allowing comparisons across ages and sex and will likely provide a better metric for tracking change over time in children and adolescents, regardless of body size and age.