Aerobic exercises in group settings, such as swimming, running and dancing, are the most effective for relieving symptoms of depression, according to an umbrella review and data synthesis of the available evidence.

The All Ireland Science Media Centre asked experts to comment.

Dr Pádraic Dunne, Senior Lecturer, Centre for Positive Health Sciences, RCSI, comments: 

From my reading, the umbrella review by Munro and colleagues is a strong and credible synthesis on the role of exercise in mental health. The number of studies examined is impressive –  eighty-one meta-analyses, involving over 1,000 studies and nearly 80,000 participants. The reported moderate to small effect sizes of exercise on depression and anxiety align with what many healthcare professionals observe anecdotally and is something I have seen in my psychotherapy practice.

“However, as with all reviews and research projects there are some caveats. A significant number of the 81 reviews were rated low (21) or critically low (34) in terms of quality. This naturally introduces uncertainty in the findings, despite the authors claiming that sensitivity analyses suggested the findings were still reliable.

“However,  I believe the trend of the evidence is trustworthy; exercise (especially aerobic) is clearly beneficial for mental health. However, the magnitude of this benefit is less certain. This matters for Positive Health Science , because it supports a low-cost, agency-building intervention that integrates biological, psychological, and social health. Most people in healthcare believe that exercise is extremely beneficial for mental health – it is important to continue adding to the evidence base.”

Declaration of interest: I declare that I have no personal, professional, financial, or academic conflicts of interest in relation to this paper. I have no affiliations, collaborations, nor prior relationships with any of the authors that could have influenced my interpretation or evaluation of the work.

Dr Jeffrey Glennon, Assistant Professor at University College Dublin School of Medicine / Conway Institute, comments:

“Anxiety and depression affect up to 1 in 4 of people during their lifetime and have been highlighted during current difficult economic times and following the COVID-19 pandemic. This has especially affected our young people with 18-30 year olds reporting especially high rates of anxiety and depression. A number of studies have suggested the solution may be to move more. A new review and meta-analysis published by Australian researchers in the British Journal of Sports Medicine has investigated the impact of exercise in improving anxiety and depression in large combined sample cohorts of 19,638 and 57,930 individuals.

“Large cohort sizes dramatically reduce the chance of your findings being a fluke. Aerobic exercise (such as dancing, swimming and running) was as good, or better than medication or psychological interventions in reducing anxiety or especially depression. While it is difficult to control for which intensity or duration of exercise works best, it is clear that those with depression benefited the most from group exercise settings with a combined benefit of both exercise and social contact. What could be the mechanism behind this? A number of studies have highlighted inflammation in both anxiety and depression. Long-term exercise is associated with anti-inflammatory actions including reducing insulin resistance and reducing pro-inflammatory cytokines. This suggests that exercise should be considered amongst first-line interventions that your doctor can prescribe having strong benefits for not only physical but also mental health.

“Interestingly our clinical trial study published in Lancet Neurology in 2018 found similar; we tried graded exercise to alleviate fatigue in neurological patients. Feelings of mental and physical fatigue / low motivation are seen in those not only with depression but often co-occur with other neurological syndromes. Exercise improves this particularly when combined with psychological interventions such as cognitive behavioural therapy which helps motivate patients to stay engaged with the exercise programme.”

Declarations of interest: none received

Dr Siobhán Woods, Assistant Professor, Department of Psychology, Maynooth University, comments: 

“This review and meta-analysis adds to the existing evidence base highlighting significant benefits of physical activity for our mental health.

“Notably, while benefits of exercise were evident across the lifespan, this study identifies groups for whom exercise-based interventions may be most impactful, including young adults and post-partum women.

“The potentially additive benefit of group-based activities to mental health also seems to emerge, with increased opportunity for social connectedness.

“This echoes findings from a recent evaluation my colleagues in the MU Department of Psychology and I conducted of the Breakthrough Programme for Women, an integrated psychotherapy and group physical activity intervention, where-in participant-reported outcomes included improved mental health, greater confidence and valued peer relationships.

“Exercise-based interventions can be accessible, community-based and cost-effective, and the findings of this review further emphasise their utility as a treatment approach for symptoms of depression and anxiety.

“It is my hope that we’ll continue to see more interventions of this kind emerge in the Irish context, along with improved access to clinical services.”

“Once an adverse event has been included in the official information, it is more difficult to remove it when better information arises that shows the adverse event is NOT caused by the medicine.” 

Dr Evan Matthews, Lecturer and Researcher in the Centre for Health Behaviour Research, South East Technological University, comments:

“This new research is among the most exciting, up-to-date evidence that exercise interventions are a powerful mental health therapeutic for people with mental health diagnoses of depression and anxiety in both clinical and non-clinical contexts. This work provides ‘meta-meta-synthesis’ evidence, essentially bringing together review publications that have pooled data from high-quality experiments examining the role of structured exercise for people with depression and people with anxiety. Therefore, the findings essentially reflect global overview analyses from more than 900 studies and 66,707 people. Across all populations, exercise accounting for its many forms, is shown as an effective tool to reduce symptoms of depression. While there is less available evidence regarding anxiety, there is still meaningful effectiveness data to warrant recognition of its therapeutic importance.”

“This exciting research shows effectiveness value of exercise for depression and anxiety across the life-course, but also tells us that exercise may be most effective on depression and mental health symptoms in certain critical life stages. In this way, late adolescent into early adulthood and postnatal periods are shown as standout examples. In Ireland, these critical life stages are recognised as periods of potential vulnerability for poor mental health, and are also often associated with reduced opportunities for exercise. Exercise can mean different things to different people, but broadly involves structured bodily movement and a feeling of exertion. This new research points to an optimal value of exercise for depression and anxiety undertaken in supervised, supported and group based environments. Ultimately however, this work confirms assertions that exercise is powerful therapeutic for mental health that requires considered implementation in public and mental health services.”

Declaration of interest: Evan is co-financed by the Government of Ireland and the European Union through the ERDF Southern, Eastern & Midland Regional Programme 2021–27 and the Northern & Western Regional Programme 2021–27 as part of the TU RISE at South East Technological University (SETU). No other COIs to declare.