Going for a brisk walk or a jog when feeling down: the effect size of exercise on depression is proportional to its intensity

6. Going for a brisk walk or a jog when feeling down: the effect size of exercise on depression is proportional to its intensity

Cost: Free. Each session takes about half an hour. The hard part is that when you’re in a bad mood, moving feels the last thing you want to do — you have to push yourself to get started.

In plain terms: This study pooled data from 218 randomized trials involving over 14,000 adults with major depressive disorder. The biggest improvements were seen with brisk walking or jogging. Yoga, strength training, mixed aerobic workouts, and tai chi/Qigong also showed benefits, with fairly similar effect sizes across these activities. Generally, the higher the exercise intensity, the better the outcome; however, strength training and yoga tend to be the easiest to stick with long-term. The authors themselves note that the overall evidence quality is relatively low, but the key takeaway is that any physical activity is better than none — pick whatever type you’re most likely to keep doing.

Benefit: This result comes from combining data across 218 randomized controlled trials split into two groups, covering 495 treatment arms and 14,170 participants who met clinical criteria for major depression. A Bayesian network meta-analysis was used to compare all these different forms of exercise against each other, using standard care or placebo pills as control groups. The effect size is expressed as Hedges’ g; the more negative this value, the greater the symptom improvement. For brisk walking or jogging, the value was −0.62 (95% confidence interval: −0.80 to −0.45). Yoga came in at −0.55 (−0.73 to −0.36), strength training at −0.49 (−0.69 to −0.29), mixed aerobic exercise at −0.43 (−0.61 to −0.24), and tai chi/Qigong at −0.42 (−0.65 to −0.21). The original paper states that “the effect of exercise is directly proportional to its intensity”, meaning higher intensity yields better results. Strength training and yoga also score highest on acceptability, making them the most sustainable choices for most people.

Evidence grade: A

Sources: Noetel M, Sanders T, Gallardo-Gómez D, et al. (2024). Effect of exercise for depression: systematic review and network meta-analysis of randomised controlled trials. BMJ, 384, e075847. <https://doi.org/10.1136/bmj-2023-075847>

Notes: This finding is somewhat controversial. The authors themselves point out that only one out of the 218 studies met sufficiently rigorous design standards to rule out major bias. Using standard grading criteria, brisk walking and jogging only qualify for a “low” confidence rating, while all other exercise types receive “very low” ratings. Since participants know they’re taking part in an exercise program, placebo effects inevitably play a role, skewing results upward. Still, the overall conclusion holds up: any physical activity is better than none, intensity should be kept reasonably high, and you should choose a type you can realistically stick with over time. This section expands on the earlier advice in Section 3 to “get moving when feeling down”, but it is by no means a substitute for professional medical treatment after a proper diagnosis.