Abstract
The purpose of this study was to analyze the relationship between changes over the years in physical abilities of young people and their exercise and sports activity statistically. Samples were 17-year-olds covered in the National Statistics on Physical Fitness and Motor Ability prepared by MEXT obtained through Sports-test during the 18 years between 1980 and 1997. Changes over the years in averages of total physical fitness test scores was statistically analyzed by gender and groups divided by participation in exercise and sports and by length of time spent in exercise and sports daily. The normal distribution curves of distance running for every 10 years between 1970 and 2000 was also visually compared, together with the effect of changes over the years and that of exercise and sports activities on total physical fitness test scores for 17-year-olds by using structural equation modeling. It was found out that total physical fitness test scores continuously decreased after 1980 for all groups divided by the participation and time spent in exercise and sports daily. It was concluded that exercise and sports activities greatly affected the yearly decrease of physical ability after 1980, especially significantly declining the systemic staying power of the group that did not participate in exercise and sports daily, and that the above was one main cause of the decreasing physical ability in Japanese youth.
