Key messages
Exercise may be moderately effective compared to no therapy for reducing symptoms of depression.
The evidence suggests there is little to no difference in the reduction of symptoms of depression provided by exercise compared to those provided by psychological therapies or antidepressants, but this conclusion is based on a few small studies.
The studies measured the outcomes at the end of treatment, and most of them did not follow up participants in the longer term.
Unwanted effects from exercise were not common, affecting only a small number of participants.
What is depression?
Depression is a common illness, affecting over 100 million people worldwide. Depression can have a significant impact on people’s physical health, as well as reducing their quality of life.
How is depression treated?
Research has shown that both pharmacological treatment (antidepressant medication) and psychological therapies (i.e. talking treatments aimed at changing people's thoughts, emotions, or behaviours) can be effective for treating depression. However, many people prefer to try alternative approaches. Some health guidelines suggest that exercise could be used as an alternative treatment.
What did we want to find out?
We wanted to find out if exercise reduces the symptoms of depression and improves quality of life in people with depression, and we wanted to find out how exercise compares to medication, psychological therapy and alternative treatments. We also wanted to find out if exercise is associated with any unwanted effects and if it provides good value for money. This review updates one last published in 2013.
What did we do?
We searched for randomised controlled trials (RCTs) (i.e. studies where people are assigned to a treatment group randomly) that assessed the effectiveness of exercise for treating depression in adults (18 years of age and over). Studies had to compare exercise with either another active treatment (e.g. medication or psychological therapy) or an inactive intervention (e.g. no treatment, being put on a waiting list, or being given a placebo treatment (i.e. an inactive treatment that seems like a real treatment)). All studies had to include adults with a diagnosis of depression, and the physical activity carried out had to fit our definition of 'exercise'.
We described, evaluated and summarised the results of the studies. We made a judgement about our confidence in the evidence based on factors such as the size of the studies and the methods used to conduct them. We searched medical databases for studies up to November 2023.
What did we find?
We found 73 studies that involved at least 4985 adults with depression. The risk of bias in some of the studies was high, which lowered our confidence in the findings.
Exercise may result in a reduction in depressive symptoms compared to no therapy, although the evidence about long-term effects is uncertain.
There is probably little to no difference in depressive symptoms between people undertaking exercise and those receiving psychological therapy. There may be little to no difference in depressive symptoms between people doing exercise and those taking antidepressants.
There does not seem to be a difference between the different interventions in terms of their acceptability as treatments, as measured by the number of participants completing the studies.
The benefits of exercise compared to no therapy, psychological therapy or pharmacological treatments on quality of life are inconsistent and uncertain.
Adverse events from exercise were not common. The small number of participants who experienced them usually reported muscle and joint problems or worsening of depression.
What are the limitations of the evidence?
Many of the studies included a relatively small number of people and had a high risk of bias in terms of the research methods they used. Also, most studies only assessed the effects of exercise over a short period of time. These factors limit our confidence in the findings of the review. Future research should focus on improving the quality of the studies, working out which characteristics of exercise are effective for different people, and ensuring different types of people are included in the studies so that health equity issues can be considered.