Fig. 3

Regression analysis of the starting time of the postural muscles for age in children and mean value of the time in each age group. *p < 0.05, **p < 0.01. Small open circles indicate the starting time of the posterior postural muscles in all children aged 3–14 years. Filled squares indicate the mean starting time in each childhood age group, and open squares indicate the mean starting time in young adults (YA). The starting time for TA in adults was not included in this analysis because the activation rate was very low (< 10%). Daggers indicate significant differences relative to the burst onset of the deltoid anterior. †p < 0.05. Sharps indicate significant differences relative to adults. #p < 0.05