The effects of various types of exercise on low back pain have long been debated. In this study, researchers compared the effects of recreational physical activity with the effects of specific back exercises. This was a secondary analysis of data from a previously published clinical trial that involved 681 people with low back pain (Spine 2002; 27:2193); half of these patients had been symptomatic for longer than 1 year.
Patients were assessed at baseline and then serially during 18 months. In a cross-sectional analysis, performance of specific back exercises was positively associated with pain and functional disability, whereas general exercise (e.g., walking and other recreational activities) was inversely associated with pain and disability. In longitudinal analyses (i.e., looking at 18-month outcomes as a function of baseline activity), correlations were consistently in the same direction as the cross-sectional results, although not quite as strong. All analyses were adjusted for potentially confounding variables.
These results might surprise some readers: Specific back exercises were associated with worse outcomes in patients with low back pain, but general exercise was associated with better outcomes. However, this was an observational study, and one might question cause and effect: For example, do back exercises worsen pain, or are patients with greater pain more likely to try back exercises? Nevertheless, the consistency between the cross-sectional and longitudinal analyses raises the provocative possibility that, on average, back exercise worsens low back pain, but general activity improves it.
Reference:
Hurwitz EL et al. Effects of recreational physical activity and back exercises on low back pain and psychological distress: Findings from the UCLA low back pain study. Am J Public Health 2005 Oct; 95:1817-24.