The purposes of this study were to attempt the classification of secular contrast such as high and/or low difference among the events using the statistics of Annual Physical Fitness Surveys (APS) of Japanese elementary school children, and to investigate the relationship between the secular contrast and the historical changes of the curriculum guidelines for physical education in Japan. The statistical data that was used in this study was the data of physical fitness surveys to 1964-2012 years of 11-year-old boys and girls that have been published by the Ministry of Education, Culture, Sports, Science and Technology (MEXT). Four measurement items, which were grip strength, 50 m sprint, long-distance running and softball throwing were analyzed in order to clarify the secular contrast. Additionally the variability of secular changes was investigated with the comparison of secular variance ratio between the APS (sample survey) and the population survey of National Survey of Physical Fitness, Athletic Performance and Exercise Habits (complete survey) conducted by MEXT since 2008. Cluster analysis was applied in order to classify the contrast pattern. Then, two-way ANOVA were applied to extract the difference of measurement items. Variability of secular changes in APS was larger than that of population survey. Three-point moving average variation in APS was close to population survey. It suggest that three-point moving average score is useful from the view point of annual variation. Both boys and girls, physical fitness pattern of Four measurement items were classified into five clusters：cluster of 1965-1971, 1972-1980, 1981-1994, 1995-2003, and 2004-2011 for boys, that of 1965-1968, 1969-1980, 1981-1993, 1994-2003, and 2004-2011 for girls. Patterns that have been classified by cluster analysis was similar to the historical change of the curriculum guidelines. In two-way ANOVA, the presence of the secular contrast effects of the two factors is shown revealed. The conclusion of this study, the cluster classification and secular contrast has been suggested that historical change of the curriculum guidelines is affecting.
Present study investigated habitual behavior, physical activity-related characteristics and psychological characteristics associated with multi-number of days absent in 130 local public school children of 4-6 grades. As a result, low level of fitness and long screen time (watching TV and DVDs, playing with computer game, and operation of mobile phone or personal computers) were significantly associated with multi-number of days absent, respectively, even taking into account the habitual behavior and psychological characteristics. In conclusion, it might be suggested that the unfavorable physical activity-related characteristics were strongly related to multi-number of days absent in school children in the present study. It was considered that these results should be verified by longitudinal research in larger sample and intervention studies in future.
From analysis of 10 years of data from the MEXT New Physical Fitness Test, we derived an answer to when physical fitness training should begin. The current proposals using the Miyashita Model are based on 30 year-old data, and need to be substantially updated. 1) The current model's optimal time for physical fitness development is too late； following this model will result in missing the optimal period for training. 2) There is a large difference in the optimal training period between sexes. It is necessary to propose different models for boys and girls. 3) There is large potential for physical development in early childhood. Especially in endurance, agility, flexibility, etc., the optimal training period may occur during early childhood. 4) For strength training, the optimal age for boys is 12.6 years old, with a range of 10.6-14.9 years old. For girls, the optimal age is 10.6, with a range from 7.65-13.55 years old. Both girl's and boy's optimal age is significantly earlier than is suggested by current models. 5) Endurance training for both boys and girls should begin from 9 years of age.