Physical performance in relation to age, sex, birth order, social class, and sports activities of preschool children.

Physical performance of 1,194 preschool children, ages 43 to 84 mo. was related to characteristics of physical growth, cognitive performance, and social variables. Correlations between measures of physical growth and physical performance and between motor and cognitive performance were positive and significant. Physical fitness, body coordination, and manual dexterity improved across age groups. Significant sex differences were found, although boys exceeded on some measures and girls on others. Children with older sisters or brothers performed better than only or first-born children, and children who participated in sports activities outside school outperformed those who did not.