Sports participation during adolescence: a shift from environmental to genetic factors

Purpose: A twin design was used to assess the relative contribution of genetic and environmental influences on the variation in sports participation of Dutch male and female twins between the ages of 13 and 20 yr. Methods: Survey data from 2628 complete twin pairs were available (443 male and 652 female monozygotic twin pairs, 377 male and 434 female dizygotic twin pairs, and 722 opposite-sex twin pairs). Subjects were classified as participating in sports if they engaged in competitive or noncompetitive leisure-time sports activities with a minimal intensity of 4 METs for at least 60 min-wk