This study aimed to clarify the effect of play frequency and exercise when at preschool and childhood ages on the exercise habits and physical fitness of those who are currently adolescents. Health young men from 15 to 21 years old participated in the physical fitness test of the Ministry of Education, Culture, Sports, Science and Technology after answering questions about current exercise habits and frequency of play and exercise at their preschool and childhood ages. Significant relationships among frequency of play at preschool age and exercise in childhood and current exercise habits were observed. Although no significant difference was found in the physique among the four groups, which differed in the frequency of play and exercise in early childhood and childhood, performance on the 50-m dash, standing long jump, handball throw, and 20-m shuttle run were significantly superior in groups with higher frequency of play and exercise.

Aim This study clarified the characteristics of life habits of obese Japanese male students at the National Colleges of Technology, Japan. Materials and methods Healthy students aged 15-19 years answered a questionnaire containing 21 items on the following five categories of life habits: general exercise, meals, sleeping, leisure activity and illness or injury history. The subjects were divided into three groups based on the criteria of body mass index (BMI) and body fat percentage (%BF): non-obese (%BF<20%, n=420), overweight obese (%BF>20% and BMI>25, n=99), and hidden obese (%BF>20% and BMI<25, n=60). The mean differences in waking time, bedtime and amount of time spent walking, sleeping and watching TV per day were examined using one-way analysis of variance (ANOVA) and chi-square tests for each item. Results The overweight obese and hidden obese groups engaged in less exercise time, were more likely to eat until they were full at meals and were less likely to eat between meals or late at night than the non-obese group. In addition, the non
-obese group had significantly later waking times and significantly less TV-watching time than the overweight obese group. There were no significant differences with respect to leisure activity and illness or injury history among the three groups. Many students in all groups had regular waking times and were not performing any leisure activities. Conclusion The findings suggest that obese students may need further guidance to help them maintain a healthy life and appropriate weight.

部活動に参加する生徒は、体力向上のためのトレーニング時間が充実している。一方、運動部に所属しない生徒の体力については、授業以外で運動時間が確保することが困難な状況にある。本研究では、男子生徒を対象に、運動部所属群と非所属群（統制群）の体力テストの記録を比較し、運動部所属の有無が体格や体力に及ぼす影響について検討することを目的とした。その結果、部活動に所属していない生徒に対しては、全身持久力をはじめとする体格や体力全般の発育発達を促す教育の充実が重要であることが示唆された。