成山 公一

A longitudinal study was conducted to determine the physical maturity characteristics of athletes engaged in the following extracurricular sports activities over the three-year junior high school period: basketball (N=40), baseball (N=130), volleyball (N=54), soccer (N=86) and a non-athletic group (N=37) which did not participate in sports.<BR>Each athlete's maturity was determined from the age of maximum increment in height (MIA) of each individual. Longitudinal stature measurements were recorded annually in April for 12 years period from 6 to 18 years of age.<BR>The study yielded the following results:<BR>1. The MIA distributions of all the sporting groups were distinctly larger than that of the non-athletic group, increasing with each chronological age step on the distance curve and annual increase in height curve. The MIA mean value for the soccer group was significantly higher (P<0.05) than those of the non-athletic and all the other sporting groups.<BR>2. The soccer group was significantly slighter (P<0.05) in stature than all the other sporting groups.<BR>3. Subjects who played baseball throughout high school reached physical maturity earlier than those who only played throughout junior high school. However, those who continued to play soccer throughout high school reached maturity later than those who only played throughout junior high school.