Associations among motor competence, health-related fitness, and physical activity in children: A comparison of gold standard and field-based measures.

This study compared the associations among motor competence, health-related fitness, and physical activity measured by gold standard and field-based methods in children. A total of 248 first-grade children (153 boys) aged 6-7 years participated in the study. Motor competence was assessed using the Test of Gross Motor Development, Second Edition (TGMD -2). Gold standard measures were percent body fat using dual-energy X-ray absorptiometry, peak oxygen uptake per weight using a gas analyser, and moderate-to-vigorous physical activity using accelerometers. Field-based measures were body mass index, maximum speed during progressive running on a treadmill, and a physical activity questionnaire. Multiple regression analysis adjusted for age and sex was used to examine the associations of motor competence with one of the health-related variables and compared differences by measurement method. The results indicated that field-based measures models showed lower associations (R2 = 0.02-0.17) than the gold standard (R2 = 0.21-0.27) and lower standardised regression coefficients for sex and motor competence, except for maximum speed. In conclusion, gold standard measures resulted in stronger associations between motor competence, and health-related fitness and physical activity in children. Examining the contribution of motor competence in children's health using field-based tests can underestimate it.