By Rachel McDonald, the Australian Science Media Centre

Exercise should be one of the first treatments considered for depression, according to the evidence from over 1000 studies on the subject. Australian and international researchers this week published an umbrella review - a review of previous meta-analyses on the effectiveness of exercise for treating mental health - spanning just over 1000 studies in total. They say the main consensus is in; exercise interventions of any kind have the capacity to mitigate the symptoms of depression, and to a lesser extent, anxiety, across all population groups.

Aerobic exercise, such as running, swimming, or dancing, had the clearest positive impact on depression and anxiety symptoms, the researchers say, and group and supervised sessions were more effective for depression symptoms while shorter, lower intensity exercise seemed to be best for those with anxiety.

The review was led by James Cook University PhD student Neil Munro, who said the impact of exercise differed between different groups of the population.

"There were particularly strong effects for people with diagnosed depression and anxiety disorders. For depression specifically, the greatest benefits were seen in two key groups: people aged 18 to 30 and postnatal women."

"This finding is especially significant given how underserved these populations often are in accessing traditional mental health care."

Professor Anna Whittaker from the University of Stirling's Centre for Research & Innovation in Sport told the UK Science Media Centre that the research "shows there is a substantial weight of evidence to encourage health professionals to prescribe exercise as a treatment for some people with depression and anxiety."

She said the included studies involved both people with diagnosed depression and anxiety as well as those with undiagnosed symptoms, and it appeared the impact of exercise was more prominent for those experiencing what could be considered milder symptoms.

On the other end of the spectrum, Honorary Professor David Curtis from the University College London told the UK SMC that it was likely this research was less relevant for people with the most severe anxiety and depression symptoms.

“The main limitation with this study is that the only patients included were those who were willing to be entered into a randomised trial of exercise treatment," Prof Curtis said.

"Patients with more severe illness would presumably have preferred other treatments which are readily available, such as antidepressants, and would simply not have volunteered to participate in the research."

He said the evidence did not show that exercise would always be an effective treatment, but that it was "helpful for patients who are well enough to attempt it as a form of treatment."

While the study authors conclude the impact of exercise could be "comparable with or exceeding traditional pharmacological or psychological interventions," Dr Brendon Stubbs from King's College London said the evidence for exercise outperforming medications or talk therapy did not come from high-quality studies.

"This review does not include head-to-head trials against pharmacotherapy or psychotherapy, and 87% of the included meta-analyses are rated as low or critically low quality," Dr Stubbs said.

"These factors undermine this statement, especially when making theoretical comparisons with typically much higher quality medication/psychotherapy trials/papers."

He said the evidence did support exercise as a comparably effective treatment to other options.

"What we do know from head-to-head trials or network meta-analyses is that exercise, medication and psychotherapy generally show similar effect sizes in mild cases, rather than one clearly outperforming the others."

Prof Whittaker said while it was important for people to consider exercise as a potential treatment for their mental health, medications and psychotherapy are still important options.

"Traditional medication and talking therapies can still be very helpful for some individuals and should not be discontinued abruptly without taking medical advice, but patients should also talk to their GPs about all their treatment options, to see if exercise prescription could be a potential treatment," she said.

She said research like this can help GPs feel more confident to suggest exercise interventions as a legitimate option.

Dr Stubbs said people looking for treatment for depression and anxiety symptoms could consider exercising either as their first option or in conjunction with other treatments.

“The key message to the public or people with anxiety or depression is that exercise is a credible, evidence-based option that can sit alongside medication and talking therapies, and in some cases be an effective first step, particularly when tailored to individual preferences and circumstances," he said.

You can read more about the study here.

You can read the full UK Expert Reaction here

This article originally appeared in Science Deadline, a weekly newsletter from the AusSMC. You are free to republish this story, in full, with appropriate credit.

Contact: Rachel McDonald

Phone: +61 8 7120 8666

Email: info@smc.org.au