Fig. 3

The ACE regression model Note: Dashed lines between the latent A, C, and E components for the early motor development traits and for the exercise behaviors are single headed arrows denoting the regression relations. Continuous double headed arrows denote the correlation between the two motor development traits and the correlations between the residuals of the latent A (ra7 - ra14), C (rc7 – rc14), and E (re7 – re14) components for exercise behavior at the various ages. MD-FS, the factor score of motor development before age 2; GM5, gross motor development at age 5; MET7, MET10, MET12, and MET14 represent the voluntary exercise behavior at each age (7, 10, 12, and 14 years)