	East Japan (n = 75)	SOS correlation	West Japan (n = 104)	SOS correlation
Experience of exercise
history of exercise in elementary school	36 (48.0)	―	64 (61.5)	―
no history of elementary school exercise	39 (52.0)	―	40 (38.5)	―
history of exercise in junior high school	31 (41.3)	―	77 (74.0)^††	―
no history of junior high school exercise	44 (58.7)	―	27 (26.0)	―
history of exercise in high school	20 (26.7)	―	49 (47.1)^††	―
no history of high school exercise	55 (73.3)	―	55 (52.9)	―
history of exercise after graduating from high school	9 (12.0)	―	34 (32.7)^††	―
no exercise history after graduating from high school	66 (88.0)	―	70 (67.3)	―
history of exercise	47 (62.7)	―	92 (88.5)^††	―
no history of exercise	28 (37.3)	―	12 (11.5)	―
Outdoor sports experience
history of outdoor sports in elementary school	14 (18.7)	―	11 (10.6)	―
no outdoor sports history in elementary school	61 (81.3)	―	93 (89.4)	―
history of outdoor sports in junior high school	14 (18.7)	―	24 (23.1)	―
no outdoor sports history in junior high school	61 (81.3)	―	80 (76.9)	―
history of outdoor sports in high school	9 (12.0)	―	16 (15.4)	―
no outdoor sports history in high school	66 (88.0)	―	88 (84.6)	―
history of outdoor sports after graduation from high school	1 (1.3)	―	7 (6.7)	―
no outdoor sports history after graduation from high school	74 (98.7)	―	97 (93.3)	―
history of outdoor sports	25 (33.3)	―	39 (37.5)	―
no history of outdoor sports	50 (66.7)	―	65 (62.5)	―
Exercise time (h)
Elementary school	106.6 ± 209.2	0.04	253.8 ± 325.6**	0.364**
Junior high school	199.4 ± 293.8	0.011	484.9 ± 409.9**	0.151
High school	122.0 ± 274.9	0.154	282.8 ± 348.9**	0.394**
Total	428.0 ± 592.1	0.091	1021.5 ± 828.9**	0.383**
Exercise intensity points
Elementary school	2.7 ± 3.6	0.206	2.7 ± 2.7	0.260**
Junior high school	4.1 ± 5.9	0.088	2.9 ± 2.2	0.308**
High school	2.4 ± 4.8	0.126	1.8 ± 2.1	0.412**
Total	9.2 ± 11.1	0.169	7.4 ± 5.2	0.435**