The purpose of this study was to identify contributors that are beneficial for both physical fitness and academic achievement in children. To achieve this, multiple factors were investigated in the home environment. The study participants consisted of 437 children in the sixth grade of elementary school. Results from their physical fitness and academic tests were obtained. In addition to physical fitness and academic achievement, the average of physical fitness and academic achievement by T-score was calculated and used as the High physical fitness and high academic achievement score. A 68-item questionnaire on home environment was completed by the children's parents or caregivers, and the results were linked to data obtained for physical fitness and academic performance. Single-correlation analysis was conducted with physical fitness, academic achievement, high physical fitness and academic achievement scores. Factors in the home environment that were significantly correlated were also extracted. Multiple regression analysis was conducted with home factors set as the independent variables and the three ability ratings set as dependent variables. Results from the analysis suggested that parent-child involvement in exercise and sport as well as the father's physical competence strongly correlated with an improvement in physical fitness. Factors relating to socioeconomic status, such as the parents educational level as well as expectations for the child to perform well academically, was strongly correlated with academic performance. In addition, in terms of both physical fitness and academic achievement, the parents' educational background, the father's physical competence, and the frequency of parent-child conversations about athletic sports have a strong influence on the child's ability to perform well.

This study clarified the distribution characteristics of the measured value of body support duration in preschool children, which has been measured for many years, and the correspondence between mean and median, and showed key points from the aspect of correctly evaluating the muscular endurance of individual children in childcare facilities. A total of 4,196 boys and girls aged 4 to 6 years were measured. It was reconfirmed that the measured value of body support duration used for muscular endurance evaluation in preschool children was not normally distributed. From examination of the correspondence between mean and median, the central tendency representative value, in the muscular endurance evaluation of preschool children by body support duration, and the use of the median is appropriate in a correct evaluation reflecting the relative rank. When estimating the median from the mean referring to the correspondence between the two even in comparative data in which the median was not revealed, it was indicated that it was possible to make a correct evaluation reflecting the relative rank in the future. In the evaluation of muscular endurance in preschool children based on body support duration, the percentage of underestimation caused by the mean standard can be corrected by using the median. Such key points enable the evaluation of muscular endurance of more appropriate individuals based on relative rank, and are necessary for subsequent appropriate assistance of each child, especially in childcare facilities.