In this study we examined the association between longitudinal changes in schoolchildren＇s
physical strength with their build, health habits, and psychophysical health index scores.
Students (n= 195) were followed for three years, from the fifth to the eighth grade. Setting as a
baseline the students＇ results on the Ministry of Education, Culture, Sports, Science and
Technology＇s new physical strength test, we extracted data on those students whose physical
strength relatively improved (improved group: 28 boys, 53 girls) and on those whose strength
relatively declined (declined group: 15 boys, 16 girls). Build, health habits, and psychophysical
health index scores were compared between the two groups. It was found that, although there
were no significant differences in eating habits or sleeping habits between the two groups,
compared to the improved group, the declined group was more likely to be either obese or
underweight, have short durations of intense exercise and total exercise, and longer duration of
watching television or videos. The declined group also showed poorer psychological health
status, such as lower self-efficacy and higher anxiety.
These findings indicate that children with good exercise habits, such as consistently
engaging in a adequate physical activities that include intense exercise, will have improved
physical strength outcome over time, whereas those children with few regular exercise habits
and whose strength will not improve over time, will show outcomes such as polarization of
body weight (obesity and underweight tendencies) and poorer psychological health status.