A lower-quality, qualitative systematic review found no clear differences between different exercise regimens, including no differences between supervised exercise and home exercise programs in three trials618. A more detailed meta-regression that analyzed potential predictors
of greater effectiveness was conducted by the authors of the Cochrane review615. Compared to
home exercises only, it found improved pain scores with individually designed programs (5.4 point improvement in pain scores, 95% credible interval 1.3 to 9.5), supervised home exercise (6.1 points, credible interval -0.2 to 12.4), group exercise (4.8 points, 95% credible interval 0.2 to 9.4 points), and individually supervised programs (5.9 points, 95% credible interval 2.1 to 9.8 points). High-dose exercise programs (20 or more hours of intervention time) were not superior to low-dose programs. Interventions that included additional non-invasive therapy were superior (5.1 points, 95% credible interval 1.8 to 8.4 points) to those without additional non-invasive therapy. The exercise regimens that were most effective used stretching and strengthening, though there was some overlap with other types of exercise (aerobic, mobilizing, or other specific exercise methods). The meta-regression suggested that an intervention incorporating all of the features of an effective exercise regimen would improve pain scores by 18.1 points (95% credible interval 11.1 to 25.0 points) compared to no treatment and by 13.0 points (95% credible interval 6.0 to 19.9 points) compared to other non-invasive treatment. Function would improve by 5.5 points (95% credible interval 0.5 to 10.5) compared to no treatment and by 2.7
points (95% credible interval -1.7 to 7.1) compared to other non-invasive treatment. No trials of such an intervention are available to confirm these estimates.
For acute low back pain, a higher-quality systematic review included one higher-quality trial that found marginal differences between the McKenzie method and flexion exercises (mean
differences=2 points on a 0 to 100 scale) for acute pain, though a second, lower-quality trial found the McKenzie method associated with large benefits on short-term (5 days) disability (mean difference=-22 points on a 0 to 100 scale, 95% CI -26 to -18)619. For chronic low back
pain, there were no clear differences between the McKenzie method and either flexion exercise or strengthening exercises (one trial for each comparison).
Harms
One systematic review attempted to evaluate adverse events associated with exercise therapy, but found insufficient evidence to generate reliable estimates618. It found 29 of 51 trials did not
report adverse events at all and nine others gave insufficient information on adverse events. Reported adverse events include two myocardial infarctions (neither thought related to exercise) and increased pain.
Costs
Two trials calculated cost-effectiveness ratios for exercise therapies. The UK BEAM trial found the addition of exercise associated with an incremental cost-effectiveness of £8300/QALY (about $16019/QALY) relative to best care, though exercise was dominated by the combination of exercise and manipulation (more costly and less effective)629. Another British trial estimated
an incremental cost-effectiveness of £3,010/QALY (about $5,809 U.S./QALY) for physiotherapy relative to physiotherapy advice alone, but a high likelihood of no significant differences
between interventions636.
Two trials compared costs between exercise programs and usual care. One found no
significant cost differences related to health services, equipment, and days off work between a progressive exercise program and usual primary care633. A cost-minimization analysis from
another trial found no differences in total costs (direct and indirect) between both standard or intensive physical therapy (including exercise) and usual care637.
Three other trials included cost-benefit analyses of exercise therapy versus other interventions. For acute low back pain, one trial found no significant cost difference between exercise and either bed rest or usual activities (usual activities associated with more rapid recovery in this trial)349. Another trial found exercise associated with greater costs compared to providing a self-
care education book ($437 versus $153), and only marginally better outcomes367.
Studies that compared costs between exercise therapy and spinal manipulation are discussed in the spinal manipulation section.
Summary of evidence
• For acute low back pain, evidence on efficacy of exercise relative to placebo or no treatment is somewhat inconsistent, though most trials found no benefit (level of evidence: fair).
• For chronic low back pain, numerous trials found exercise moderately superior to placebo for pain relief and work-related outcomes, though exercise was not associated with beneficial effects on functional outcomes (level of evidence: good).
• For either acute or chronic low back pain, numerous trials found no consistent, clinically significant differences between exercise therapy and other non-invasive interventions (level of evidence: good).
• Exercise regimens incorporating features such as individual tailoring, supervision, stretching, and strengthening were associated with the best outcomes in a meta-regression analysis (level of evidence: fair).
•
There are no clear differences in four trials (two higher-quality) between the McKenzie method and flexion or strengthening exercises, with only one lower-quality trial finding the McKenzie method superior (level of evidence: fair).Recommendations and findings from other guidelines
• The AHCPR guidelines found that low-stress aerobic exercise can prevent debilitation due to inactivity during the first month of symptoms and help patients with acute low back problems return to usual functioning (strength of evidence: C).
• The AHCPR guidelines suggest that low-stress aerobic exercise programs can be started during the first 2 weeks for most patients with acute low back problems (strength of evidence: D).
• The AHCPR guidelines suggest that conditioning exercises for trunk muscles are helpful for patients with acute low back problems, particularly if symptoms persist, but may aggravate symptoms more than aerobic exercise in the first 2 weeks (strength of evidence: C). • The AHCPR guidelines found no evidence that back-specific exercise machines provide
benefit over traditional exercise (strength of evidence: D).
• The AHCPR guidelines found no evidence to support stretching of the back muscles for acute low back problems (strength of evidence: D).
• The AHCPR guidelines suggest that gradually increasing exercise quotas result in better outcomes than telling patients to stop exercising if pain occurs (strength of evidence: C). • The VA/DoD guideline recommendations for exercise are similar to the AHCPR
recommendations.
• The UK RCGP guidelines concluded that it is doubtful that specific back exercises produce significant improvement in acute low back pain, or that it is possible to select which patients will respond to which exercises (strength of evidence: ***).
• The UK RCGP guidelines found some evidence that exercise programs and physical
reconditioning can improve pain and function in patients with chronic low back pain (strength of evidence: **).
• The UK RCGP guidelines found theoretical arguments for starting exercise programs at around 6 weeks after start of symptoms (strength of evidence: *).
• The European COST guidelines recommend against advising specific exercises for acute low back pain.
• The European COST guidelines recommend supervised exercise as a first-line treatment for chronic low back pain. They suggest exercise programs that don’t require expensive training machines, the use of a cognitive-behavioral approach with graded exercises, and quotas. Group exercises are suggested as a low-cost option. The guidelines provide no
recommendations on specific types of exercise, and suggest the patient and therapist could best determine that.
Hydrotherapy
For this review, we defined hydrotherapy as exercises performed in a pool or other water-based setting. In contrast to spa therapy and balneotherapy, which involve immersion in thermal mineral water, hydrotherapy generally employs normal (or chlorinated) tap water.
Results of search: systematic reviews
We found no systematic reviews evaluating efficacy of hydrotherapy for low back pain. Results of search: trials
From 88 potentially relevant citations, we identified three lower-quality trials of hydrotherapy for chronic low back pain638-640.