Depression and anxiety affect millions of people worldwide^[1].

While treatments^[2] such as medication^[3] and psychotherapy^[4] (sometimes called talk therapy) can be very effective, they’re not always an option^[5]. Barriers include^[6] cost, stigma, long waiting lists for appointments, and potential drug side effects.

So what about exercise? Our new research, published today^[7], confirms physical activity can be just as effective for some people as therapy or medication. This is especially true when it’s social and guided by a professional, such as a gym class or running club.

Let’s take a look at the evidence.

What we already knew

Physical activity^[8] has long been promoted as a treatment option^[9] for anxiety and depression, largely because it helps release^[10] “feel good” chemicals in the brain which help boost mood and reduce stress.

But the evidence can be confusing. Hundreds of studies with diverse results^[11] make it unclear how much exercise^[12] is beneficial, what type, and who it helps^[13] most.

Over the past two decades, researchers have conducted^[14] dozens of separate meta-analyses (studies that combine results from multiple trials) examining exercise^[15] for depression and anxiety. But these have still left gaps in understanding how effective exercise is for different age groups and whether the type of exercise matters.

Many studies^[16] have also included participants with confounding factors (influences that can distort research findings) such as other chronic diseases, for example, diabetes or arthritis. This means it can be hard to apply the findings more broadly.

What we did

Our research aimed to resolve this confusion by conducting a “meta-meta-analysis”. This means we systematically reviewed the results of all the existing meta-analyses – there were 81 – to determine what the evidence really shows.

Together, this meant data from nearly 80,000 participants across more than 1,000 original trials.

We examined multiple factors that might explain why their results varied. These included differences in:

• who they studied (for example, people with diagnosed depression or anxiety versus those just experiencing symptoms, different age groups, and women during pregnancy and after birth)

• what the exercise involved (for example, comparing aerobic fitness to resistance training and mind-body exercises, such as yoga; whether it was supervised by a professional; intensity and duration)

• whether the exercise was individual or in a group.

We also used advanced statistical techniques to accurately isolate and estimate the exact impact of exercise, separate from confounding factors (including other chronic diseases).

Our data looked at the impact of exercise alone on depression and anxiety. But sometimes people will also use antidepressants and/or therapy – so further research would be needed to explore the effect of these when combined.

What did the study find?

Exercise is effective at reducing both depression and anxiety. But there is some nuance.

We found exercising had a high impact on depression symptoms, and a medium impact on anxiety, compared to staying inactive.

The benefits were comparable to, and in some cases better than, more widely prescribed mental health treatments, including therapy and antidepressants^[17].

Importantly, we discovered who exercise helped most. Two groups showed the most improvement: adults aged 18 to 30 and women who had recently given birth.

Many women experience barriers^[18] to exercising after giving birth, including lack of time, confidence or access to appropriate and affordable activities.

Our findings suggest making it more accessible could be an important strategy to address new mothers’ mental health in this vulnerable time.

How you exercise matters

We also found aerobic activities – such as walking, running, cycling or swimming – were best at reducing both depression and anxiety symptoms.

However, all forms of exercise reduced symptoms, including resistance training (such as lifting weights) and mind-body practices (such as yoga).

For depression, there were greater improvements when people exercised with others and were guided by a professional, such as a group fitness class.

Unfortunately, there wasn’t available data on group or supervised exercise for anxiety, so we would need more research to find out if the impact is similar.

Exercising once or twice a week had a similar effect on depression as exercising more frequently. And there didn’t seem to be a significant difference between exercising vigorously or at a low intensity – all were beneficial.

But for anxiety, the best improvements in anxiety symptoms were when exercise was done:

• consistently, for up to eight weeks, and

• at a lower intensity, such as walking or swimming laps at a gentle pace.

So, what does all this mean?

Our research shows exercise is a legitimate and evidence-based treatment option for depression and anxiety, particularly for people with diagnosed conditions.

However, simply telling patients to “exercise more” is unlikely to be effective.

The evidence shows structured, supervised exercise with a social component^[19] is best for improving depression and anxiety. The social aspect and the accountability may help^[20] keep people motivated.

Clinicians should keep this in mind, offering referrals to specific programs – such as aerobic fitness classes or supervised walking and running programs – rather than general advice.

The findings also suggest this kind of exercise can be particularly effective when targeted to depression in younger adults and women who’ve recently given birth.

The takeaway

For people who are hesitant about medication, or facing long waits for therapy, supervised group exercise may be an effective alternative. It’s evidence-based, and you can start any time.

But it’s still best to get advice from a professional. If you have anxiety^[21] or depression^[22] symptoms, you should talk to your GP or psychologist. They can advise where exercise fits in your treatment plan, potentially alongside therapy and/or medication.

References

1. ^{^} millions of people worldwide (doi.org)
2. ^{^} treatments (doi.org)
3. ^{^} medication (doi.org)
4. ^{^} psychotherapy (doi.org)
5. ^{^} not always an option (doi.org)
6. ^{^} include (doi.org)
7. ^{^} published today (bjsm.bmj.com)
8. ^{^} Physical activity (doi.org)
9. ^{^} treatment option (doi.org)
10. ^{^} release (doi.org)
11. ^{^} with diverse results (doi.org)
12. ^{^} exercise (doi.org)
13. ^{^} who it helps (doi.org)
14. ^{^} have conducted (doi.org)
15. ^{^} examining exercise (doi.org)
16. ^{^} studies (doi.org)
17. ^{^} therapy and antidepressants (doi.org)
18. ^{^} barriers (doi.org)
19. ^{^} with a social component (doi.org)
20. ^{^} may help (doi.org)
21. ^{^} anxiety (www.beyondblue.org.au)
22. ^{^} depression (www.beyondblue.org.au)