Body size and shape characteristics for Cooper's 12 minutes run test in 11-13 years old Caucasian children: an allometric approach.

Background: The Cooper Test, is a field test, simple and useful in the school context. The aim of this research was the definition of the trend in Cooper endurance test along with the growth. In particular, through the scaling method (allometric).

Methods: A total of 556 of European sedentary children aged 11-13 years (282 boys; 274 girls) were involved. All subjects were evaluated through the Endurance Cooper test (12 min run test). To identify the most appropriate body size and shape characteristics as well as any categorical differences (sex, age) associated with the measure of the Cooper test, a multiplicative model with allometric body-size components was applied.

Results: The multiplicative model relating to the Cooper test and the body-size components was: Cooper test = a · mass-0.325 · height0.878 with the mass and height exponents being k1=-0.325 (SEE=0.40) and k2= 0.878 (SEE=0.141), respectively. The adjusted coefficient of determination (adj R2) was 32.3%, with a log-transformed error ratio of 0.136 or 14.5% having taken antilogs. Significant differences in the constant 'a' parameter were identified by sex (P<0.001) and age (P<0.001) while the interaction of sex per age was not significant (P=0.761).

Conclusions: The results suggested that the scaling method identified the optimal height-to-body mass ratios associated with Cooper endurance test corresponding to ectomorph body shape. Furthermore, growth fluctuations become important to avoid alarming judgment in case children will be poorly evaluated.