Table 2.

The association between sports activities and LBP

Type of sports	No. (%)	LBP (%)	Odds ratio	95% CI	P value	Severe LBP (%)
Swimming	5,662 (19)	27.5	1.41	1.27−1.55	<0.001	17.5
Basketball	3,726 (12)	37.9	1.79	1.61−1.99	<0.001	22.9
Soccer	3,534 (12)	34.9	1.77	1.56−2.02	<0.001	22.8
Baseball	3,525 (12)	37.5	1.82	1.60−2.06	<0.001	21.9
Tennis	2,097 (7)	34.3	1.24	1.09−1.42	<0.01	15.3
Wind-instrument music	1,872 (6)	37.3	1.32	1.15−1.51	<0.001	12.8
Table tennis	1,486 (5)	34.7	1.05	0.89−1.21	0.63	18.1
Volleyball	1,445 (5)	46.6	2.14	1.86−2.46	<0.001	21.6
Athletics	1,324 (4)	48.6	2.18	1.89−2.52	<0.001	27.4
Kendo	993 (3)	35.5	1.39	1.18−1.65	<0.001	24.7
Karate	897 (3)	31.9	1.57	1.31−1.87	<0.001	22
Badminton	771 (3)	39.8	1.51	1.26−1.80	<0.001	25.6
Ballet	669 (2)	30.3	1.63	1.33−1.99	<0.001	17.5
Dance	582 (2)	34.7	1.75	1.42−2.15	<0.001	20
Judo	569 (2)	51.1	2.12	1.73−2.52	<0.001	31.1
Gymnastics	560 (2)	36.3	2.05	1.67−2.51	<0.001	29.4
Golf	102 (<1)	51	2.2	1.45−3.35	<0.001	27.2
Dodgeball	95 (<1)	32.6	1.59	0.95−2.55	0.08	20.8
Rugby	70 (<1)	51.4	2.58	1.56−4.27	<0.001	29
Sumo wrestling, wrestling	48 (<1)	35.4	0.85	0.42−1.71	0.65	25
Archery	23 (<1)	39.1	1.1	0.42−2.88	0.84	16.7
Total	30,050*
Sports group	21,280/26,766	34.9	1.57	1.45−1.70	<0.001	20.1
No sports group	5,486/26,766	21.3	1			3.2

The odds ratio and the severity of LBP between No Sports group and Sports group and in each sports item were calculated by multiple logistic regression analysis and χ² analysis (grade, gender, and BMI corrected)

* Repeated answers in sports items were included

Severe LBP (%) the ratio of severe LBP among subjects with a history of LBP, CI confidence interval