Background Several factors, particularly osteoporosis, obesity, and a lack of exercise, contribute to low back pain (LBP). This observational longitudinal cohort study to identify the risk factors for worsening low back pain.

Methods We sent a self-administered questionnaire and a consent form for this study to 1,450 subjects aged > 40 years in Hino, Japan. Baseline assessments of 273 individuals undergoing medical check-ups were conducted from 2014 to 2016. The subjects were divided into Group A (no change or improvement in LBP) and Group B (worsening LBP). LBP was assessed using a visual analog scale; body mass index (BMI), bone mineral density, skeletal muscle index (SMI), standing posture, and habitual exercise frequency were also evaluated. We defined, habitual exercise as nontherapeutic exercise (e.g. swimming, walking, physical exercise and work out).

Results Overall, 81.2% subjects performed habitual exercise in Group A, a greater number of subjects than the 40.8% in Group B. BMI, SMI, and bone mineral density (BMD) were not significantly different between the two groups. Lack of exercise was a significant risk factor for worsening of LBP. On the other hand, the lack of osteoporosis treatment was significantly different between subjects with worsening LBP despite habitual exercise and those who did not perform habitual exercise.

Conclusion Although habitual exercise is useful to prevent LBP, it may not necessarily be useful for those with a lack of osteoporosis treatment. Although exercise is typically posited to prevent LBP, it may not be effective in preventing LBP associated with osteoporosis.