Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials

Author: Michael Noetel1, Taren Sanders2, Daniel Gallardo-Gómez3, Paul Taylor4, Borja Del Pozo Cruz5,6, Daniel van den Hoek7, Jordan J Smith8, John Mahoney9, Jemima Spathis9, Mark Moresi4, Rebecca Pagano10, Lisa Pagano11, Roberta Vasconcellos2, Hugh Arnott2, Benjamin Varley12, Philip Parker13, Stuart Biddle14,15, Chris Lonsdale13
1 School of Psychology, University of Queensland, St Lucia, QLD 4072, Australia m.noetel@uq.edu.au.
2 Institute for Positive Psychology and Education, Australian Catholic University, North Sydney, NSW, Australia.
3 Department of Physical Education and Sport, University of Seville, Seville, Spain.
4 School of Health and Behavioural Sciences, Australian Catholic University, Strathfield, NSW, Australia.
5 Department of Clinical Biomechanics and Sports Science, University of Southern Denmark, Odense, Denmark.
6 Biomedical Research and Innovation Institute of Cádiz (INiBICA) Research Unit, University of Cádiz, Spain.
7 School of Health and Behavioural Sciences, University of the Sunshine Coast, Petrie, QLD, Australia.
8 School of Education, University of Newcastle, Callaghan, NSW, Australia.
9 School of Health and Behavioural Sciences, Australian Catholic University, Banyo, QLD, Australia.
10 School of Education, Australian Catholic University, Strathfield, NSW, Australia.
11 Australian Institute of Health Innovation, Macquarie University, Macquarie Park, NSW, Australia.
12 Children's Hospital Westmead Clinical School, University of Sydney, Westmead, NSW, Australia.
13 Australian Catholic University, North Sydney, NSW, Australia.
14 Centre for Health Research, University of Southern Queensland, Springfield, QLD, Australia.
15 Faculty of Sport and Health Science, University of Jyvaskyla, Jyvaskyla, Finland.
Conference/Journal: BMJ
Date published: 2024 Feb 14
Other: Volume ID: 384 , Pages: e075847 , Special Notes: doi: 10.1136/bmj-2023-075847. , Word Count: 328

To identify the optimal dose and modality of exercise for treating major depressive disorder, compared with psychotherapy, antidepressants, and control conditions.

Systematic review and network meta-analysis.

Screening, data extraction, coding, and risk of bias assessment were performed independently and in duplicate. Bayesian arm based, multilevel network meta-analyses were performed for the primary analyses. Quality of the evidence for each arm was graded using the confidence in network meta-analysis (CINeMA) online tool.

Data sources:
Cochrane Library, Medline, Embase, SPORTDiscus, and PsycINFO databases.

Eligibility criteria for selecting studies:
Any randomised trial with exercise arms for participants meeting clinical cut-offs for major depression.

218 unique studies with a total of 495 arms and 14 170 participants were included. Compared with active controls (eg, usual care, placebo tablet), moderate reductions in depression were found for walking or jogging (n=1210, κ=51, Hedges' g -0.62, 95% credible interval -0.80 to -0.45), yoga (n=1047, κ=33, g -0.55, -0.73 to -0.36), strength training (n=643, κ=22, g -0.49, -0.69 to -0.29), mixed aerobic exercises (n=1286, κ=51, g -0.43, -0.61 to -0.24), and tai chi or qigong (n=343, κ=12, g -0.42, -0.65 to -0.21). The effects of exercise were proportional to the intensity prescribed. Strength training and yoga appeared to be the most acceptable modalities. Results appeared robust to publication bias, but only one study met the Cochrane criteria for low risk of bias. As a result, confidence in accordance with CINeMA was low for walking or jogging and very low for other treatments.

Exercise is an effective treatment for depression, with walking or jogging, yoga, and strength training more effective than other exercises, particularly when intense. Yoga and strength training were well tolerated compared with other treatments. Exercise appeared equally effective for people with and without comorbidities and with different baseline levels of depression. To mitigate expectancy effects, future studies could aim to blind participants and staff. These forms of exercise could be considered alongside psychotherapy and antidepressants as core treatments for depression.

Systematic review registration:
PROSPERO CRD42018118040.

PMID: 38355154 DOI: 10.1136/bmj-2023-075847