We reviewed the evidence on the effect of exercise therapy in adults with low back pain lasting six weeks or less.
Low back pain is common and disabling, causing a significant burden on the individuals affected and on society. Low back pain often leads to reduced quality of life, time lost from work, and substantial medical expenses.
Exercise therapy consists of planned or structured physical activity aimed at improving or maintaining one or more aspects of physical fitness. A range of healthcare professionals provides this intervention, which is often recommended for people with low back pain. Exercise therapy aims to improve physical fitness, flexibility, stability, and co-ordination. It may also focus on training specific muscles. However, the effectiveness of exercise therapy for people with low back pain is unclear.
For this review, we included low back pain episodes that were not caused by known underlying conditions, such as infection, cancer, broken bones, or pregnancy. People participating in the studies could also have pain in their buttocks and legs, but the pain had to be mainly in the lower back. This is an update of a Cochrane Review first published in 2005.
We searched for evidence up to 18 November 2021.
We included 23 studies that involved a total of 2674 people and provided numeric information for 2637 people. Ten studies were new and 13 were included in our previous review. The studies were carried out in Europe, the Asia-Pacific region, and North America. In most studies, the population was middle-aged and included a mix of men and women. We were mainly interested in the short-term effects of exercise therapy compared to sham/placebo treatment (dummy treatment) and compared to no treatment. For this review, 'short-term' meant around six weeks after the beginning of treatment. Twelve of the 23 studies received funding from governmental or non-profit organisations. Eleven studies did not report funding sources.
Exercise therapy may be no better than sham/placebo treatment for pain relief in the short term. On average, pain intensity was 0.8 points lower on a 100-point scale (lower scores mean less pain) in the exercise group. In other words, the exercise therapy group had 1% less pain than the sham/placebo treatment group. These results are very uncertain and should be interpreted with caution, because they came from a single study with only 299 participants.
Exercise therapy may be no better than sham/placebo treatment for improving functional status in the short-term. On average, people in the exercise group scored 2 points more on a 100-point disability scale (lower scores mean less disability). In other words, the exercise therapy group had 2% worse functional status than the sham/placebo treatment group. These results are very uncertain and should be interpreted with caution, because they came from a single study with only 299 participants.
Exercise therapy may be no better than no treatment for pain relief and improved function in the short term. This finding should be interpreted with caution as it is based on two small studies with only 157 participants in total.
Few studies measured unwanted effects, and none reported any unwanted effects related to exercise therapy. We were unable to draw any conclusions on the safety of exercise therapy in people with low back pain.
Limitations of the evidence
We have very little confidence in the evidence because the studies were poorly designed and included few people.
Exercise therapy compared to sham/placebo treatment may have no clinically relevant effect on pain or functional status in the short term in people with acute non-specific LBP, but the evidence is very uncertain. Exercise therapy compared to no treatment may have no clinically relevant effect on pain or functional status in the short term in people with acute non-specific LBP, but the evidence is very uncertain. We downgraded the certainty of the evidence to very low for inconsistency, risk of bias concerns, and imprecision (few participants).
Low back pain (LBP) is the leading cause of disability globally. It generates considerable direct costs (healthcare) and indirect costs (lost productivity). The many available treatments for LBP include exercise therapy, which is practised extensively worldwide.
To evaluate the benefits and harms of exercise therapy for acute non-specific low back pain in adults compared to sham/placebo treatment or no treatment at short-term, intermediate-term, and long-term follow-up.
This is an update of a Cochrane Review first published in 2005. We conducted an updated search for randomised controlled trials (RCTs) in CENTRAL, MEDLINE, Embase, four other databases, and two trial registers. We screened the reference lists of all included studies and relevant systematic reviews published since 2004.
We included RCTs that examined the effects of exercise therapy on non-specific LBP lasting six weeks or less in adults. Major outcomes for this review were pain, functional status, and perceived recovery. Minor outcomes were return to work, health-related quality of life, and adverse events. Our main comparisons were exercise therapy versus sham/placebo treatment and exercise therapy versus no treatment.
We used standard Cochrane methods. We evaluated outcomes at short-term follow-up (time point within three months and closest to six weeks after randomisation; main follow-up), intermediate-term follow-up (between nine months and closest to six months), and long-term follow-up (after nine months and closest to 12 months); and we used GRADE to assess the certainty of the evidence for each outcome.
We included 23 studies (13 from the previous review, 10 new studies) that involved 2674 participants and provided data for 2637 participants. Three small studies are awaiting classification, and four eligible studies are ongoing. Included studies were conducted in Europe (N = 9), the Asia-Pacific region (N = 9), and North America (N = 5); and most took place in a primary care setting (N = 12), secondary care setting (N = 6), or both (N = 1). In most studies, the population was middle-aged and included men and women. We judged 10 studies (43%) at low risk of bias with regard to sequence generation and allocation concealment. Blinding is not feasible in exercise therapy, introducing performance and detection bias.
There is very low-certainty evidence that exercise therapy compared with sham/placebo treatment has no clinically relevant effect on pain scores in the short term (mean difference (MD) −0.80, 95% confidence interval (CI) −5.79 to 4.19; 1 study, 299 participants). The absolute difference was 1% less pain (95% CI 4% more to 6% less), and the relative difference was 4% less pain (95% CI 20% more to 28% less). The mean pain score was 20.1 (standard deviation (SD) 21) for the intervention group and 20.9 (SD 23) for the control group.
There is very low-certainty evidence that exercise therapy compared with sham/placebo treatment has no clinically relevant effect on functional status scores in the short term (MD 2.00, 95% CI −2.20 to 6.20; 1 study, 299 participants). The absolute difference was 2% worse functional status (95% CI 2% better to 6% worse), and the relative difference was 15% worse (95% CI 17% better to 47% worse). The mean functional status score was 15.3 (SD 19) for the intervention group and 13.3 (SD 18) for the control group.
We downgraded the certainty of the evidence for pain and functional status by one level for risk of bias and by two levels for imprecision (only one study with fewer than 400 participants).
There is very low-certainty evidence that exercise therapy compared with no treatment has no clinically relevant effect on pain or functional status in the short term (2 studies, 157 participants). We downgraded the certainty of the evidence by two levels for imprecision and by one level for inconsistency. One study associated exercise with small benefits and the other found no differences. The first study was conducted in an occupational healthcare centre, where participants received one exercise therapy session. The other study was conducted in secondary and tertiary care settings, where participants received treatment three times per week for six weeks. We did not pool data from these studies owing to considerable clinical heterogeneity.
In two studies, there were no reported adverse events. One study reported adverse events unrelated to exercise therapy. The remaining studies did not report whether any adverse events had occurred. Owing to insufficient reporting of adverse events, we were unable to reach any conclusions on the safety or harms related to exercise therapy.