Exercise as Therapy: The 2024-2025 Consensus

A landmark systematic review and network meta-analysis published in the British Medical Journal (BMJ) in February 2024 compared the effect of various exercise modalities for treating major depressive disorder against psychotherapy, antidepressants, and control conditions. The findings were striking: several exercise modalities showed moderate to large reductions in depression compared to active controls—significantly stronger than the effect of SSRIs (Selective Serotonin Reuptake Inhibitors, a common class of antidepressants) alone. Specifically, walking or jogging (g = -0.63), yoga (g = -0.55), and strength training (g = -0.49) all outperformed the effect of SSRIs (g = -0.26). The study concluded that these forms of exercise 'could be considered alongside psychotherapy and antidepressants as core treatments for depression.' This represents a significant shift in clinical guidance.

For patients with non-severe (mild to moderate) depression, the evidence is even clearer. A network meta-analysis (published 2022, widely cited in 2024-2025) compared exercise, antidepressants, and their combination. The key finding was that there were no statistically significant differences in effectiveness among the three main treatments. Exercise was similar to antidepressants (SMD = -0.12), and the combination was similar to either alone. All three were more beneficial than control conditions. The study concluded that the results 'support the adoption of exercise as an alternative or adjuvant treatment for adults with non-severe depression.' However, the review also noted that exercise interventions had higher drop-out rates compared to antidepressants, a practical consideration for clinicians.

The mechanisms by which exercise alleviates depression extend far beyond the colloquially known 'endorphin rush.' Researchers now point to several key pathways: 1) Neuroplasticity: Exercise stimulates the release of Brain-Derived Neurotrophic Factor (BDNF), a protein that supports neuron growth, survival, and repair. BDNF levels are often depleted in depressed brains, and exercise appears to restore them. 2) Inflammation Reduction: Major depressive disorder is increasingly understood to involve chronic, low-grade systemic inflammation. Regular physical activity has potent anti-inflammatory effects, counteracting this process. 3) HPA Axis Regulation: Exercise helps regulate the hypothalamic-pituitary-adrenal (HPA) axis, which controls the body's stress response and is often dysregulated in depression.

A September 2025 network meta-analysis in Nature Scientific Reports directly compared different exercise modalities for adults with clinically diagnosed depression. The ranking of efficacy was clear: Mind-body exercise (e.g., yoga, tai chi) ranked highest (94.1%), followed by Resistance training (81.0%), and then Aerobic exercise (63.9%). Mind-body exercise demonstrated superior efficacy compared to aerobic exercise (SMD = -0.43). The study emphasized that 'dose' matters less than consistency: while higher intensity showed stronger effects, even light, consistent activity like walking or gardening provided significant mental health protection compared to a sedentary lifestyle. This shifts the clinical focus from 'exercise as a chore' to 'movement as medicine.'