A survey was conducted to assess physical activity, depression, and sense of coherence among early adolescents. This study used a cross-sectional sample of 12,086 students (G5-G9) from 28 public elementary schools and 22 public junior-high-schools in Japan. A total of 9,424 students (G5-G8) were surveyed from December 2013 to December 2015 using the International Physical Activity Questionnaire (IPAQ) -short form to measure physical activity (PA), the Depression Self-Rating Scale for Children (DSRSC) for depressive symptoms, and the Sense of Coherence Scale-13-item version (SOC-13).
Vigorous PA (VPA) of the G5 boys (4h 20 min) was significantly longer than that of the G5 girls (1h 30min) and the VPA of the junior-high-school students increased significantly compared with that of the elementary-school students. The VPA of the G8 boys reached 6h 30 min, whereas that of the G8 girls approached 3h, which was a significant difference. Additionally, more junior-high-school students participated in sports-club activities than did elementary-school students.
The mean DSRS-C score of the G5 girls (10.24±5.73) was significantly higher than that of the G5 boys (9.31±5.31). No other differences by grade, were found among the elementary-school students. The depressive symptoms of the junior-high-school students indicated they had a greater risk for depression than the elementary-school students did.
The mean SOC score of the G8 boys (44.58±8.11) was higher (better) than that of the G8 girls (43.46±8.30). Furthermore, the elementary-school students' score on the SOC was higher than that of the juniorhigh-school students; the score tended to decrease as the grade increased.
