After fracturing my humerus in an arm-wrestling match, something happened that I wasn’t prepared for. For the first time in my life, I lost the ability to exercise; the one thing that had always anchored my mental health. My mood began to unravel. The only solutions I knew were the ones I’d been taught in medical school: therapy or medication. My experience isn’t unique; it reflects a much larger problem in how we currently treat depression. An estimated 1.17 billion people live with a mental disorder globally, and depression remains one of the most common. People with depression also face higher risks of other medical problems like obesity, diabetes, and heart disease. Yet our standard approach — medication, therapy, or both — leaves up to 30 to 50% of people without meaningful improvement and does little to address these physical comorbidities. This is why more holistic options, particularly exercise, deserve serious consideration. What the evidence actually shows Hundreds of clinical trials now show that exercise can significantly reduce symptoms of depression. For mild to moderate cases, its effects are generally comparable to medication or therapy. When exercise is combined with medications or therapy, the effects may even be additive. On a population level, even achieving just half the recommended amount of physical activity is linked to an 18% lower risk of developing depression. Exercise treats depression through several mechanisms at once. It boosts brain neuroplasticity by raising brain-derived neurotrophic factor (BDNF) levels, which supports new neuron growth in the hippocampus, while also reducing chronic inflammation that can harm neurons. At the same time, it helps to regulate the body’s stress-response system and strengthen psychological resilience by boosting self-esteem, self-efficacy, and social connection. Together, these biological, mental, and social changes create a more resilient brain environment that makes depression less likely to take hold or persist. However, we must be careful not to overstate the benefits. Headlines claiming that “exercise is 1.5 times more effective than medication or therapy” have spread widely, but they misrepresent the research. Those claims came from comparing effect sizes across studies of very different quality. When we look at higher-quality evidence and direct comparisons, exercise performs similarly to, but not dramatically better than, established treatments. Overhyping it risks damaging credibility in this important area of mental health. Why exercise remains rarely used If exercise is genuinely helpful, why isn’t it recommended more often? Exercise is already recommended as a first-line treatment for mild depression in major treatment guidelines. Yet a recent survey found that 92% of mental health professionals received no training in how to recommend exercise, and 41% said they never recommend it to patients. There’s a clear disconnect between the evidence, the guidelines, and clinical practice. Imagine sitting across from your psychiatrist after being diagnosed with depression. If they simply said, “Just take this antidepressant,” you’d probably expect much more, such as the specific drug, the dose, how long to take it, and what side effects to watch for. Yet when it comes to exercise, vague advice like “just go work out” is still surprisingly common. Exercise deserves the same level of thought and structure we give to medication. One practical way to do this is to use the FITT framework: Frequency, Intensity, Type, and Time. Instead of generic advice, a clinician might recommend something specific, such as: “Start with brisk walking three times a week for 20-30 minutes at an intensity where you can still talk.” This can then be adjusted as the person’s energy and fitness improve. However, even with clear recommendations, depression itself can create major barriers. Fatigue and low motivation are among the most common, often making the idea of exercise feel impossible. These challenges are real but can be overcome by starting very small, building in social support or supervision, and combining exercise with other effective treatments. What needs to change? Real change requires more than simply acknowledging that exercise works. Clinicians need better training, starting in medical school and continuing through residency and beyond. They also need practical, up-to-date guidance on how to recommend exercise effectively. That’s why I’m currently leading the development of new recommendations from the Canadian Network for Mood and Anxiety Treatments (CANMAT) and the International Society for Bipolar Disorders (ISBD) on the use of exercise in depression and bipolar disorder. Training alone isn’t enough. We also need systems that make structured exercise programs practical, including direct referral pathways to qualified exercise professionals and insurance coverage, so that supervised programs or gym access can be integrated into care as easily as medication. The evidence that exercise helps treat depression is strong. We don’t need more studies to prove it works. What we need now is to start treating it like the legitimate medical intervention that it is. This article Exercise works for depression. So why isn’t it treated like real medicine? is featured on Big Think.