Exercise, or Getting Your Body Moving

Posted on: June 16, 2025

We all know that exercise is good for both our minds and our bodies, but what I found most interesting were some new meta-analyses that suggest that exercise can be considered a treatment for mild to moderate major depression, with effects sizes similar to antidepressants and psychotherapy.  In these studies, exercise is defined as any planned and structured form of physical activity aimed at improving fitness.  In the research analyzed, exercise can be anything that gets you to move your body — walking, jogging, tennis, strength training, swimming, dance — even yoga and tai chi.  The specific type of exercise is less important than just doing something to move.  Intensity matters — so if you do a low-intensity exercise like walking, you need to do it for a longer period of time.  If you are doing a high-intensity aerobic exercise, then you don’t need to do it for as long.  Generally, doing supervised exercise (like with a trainer or in a class) is more effective than doing it by yourself.  And generally, exercise seems to be most effective for those people with higher levels of depression and if it is combined with antidepressant medication or psychotherapy. 

So how much exercise do you need to do?  Well, it depends on the intensity of your movement, but the minimum is about half an hour of walking or yoga every day.  If you walk briskly, then it is probably around 20 minutes.  Optimal amounts would be about double.  However for those people who struggle with motivation, anything is better than none — or even just decreasing sedentary activities like watching TV.

Now, how does exercise work to reduce depressive symptoms?  There are a number of interesting hypotheses, all of which have some support. 

• Depression, especially low motivation, fatigue and anhedonia, is associated with inflammation and low dopaminergic transmission; aerobic exercise decreases inflammation and increases dopamine transmission.
• When you exercise, your muscles contract, releasing cytokines and peptides.  These in term mediate communication with other organs and lead to an increase in brain-derived neurotrophic factor (BDNF).  BDNF is critical for mood regulation and healthy neurons. 
•  Structured movement over time can demonstrate incremental and tangible achievements.  These achievements can improve self-efficacy and agency, reducing the cognitive symptom of depression such as negative self-esteem. 
• Doing exercise in a class can increase social connectedness, reducing feelings of isolation and promoting a sense of community.

When thinking about embarking on an exercise program, start small and emphasize achievable goals.  One way to do this is to use the FITT framework — Frequency, Intensity, Time and Type. 

• Frequency — For optimal outcomes, aim for 3-5 times a week, but any movement is better than none.
• Intensity — Intensity can be measured in three ways. Low intensity activity is activity where you can talk and sing during the activity.  Moderate is where you can talk but not sing, and vigorous activity is where it is hard to say more than a few words.
• Time — Start with whatever is feasible for you.  Eventually, sessions of 45-60 minutes are most effective, but even 10 minutes can be helpful.
• Type — aerobic, resistance or mind-body — All types of exercise and their combinations can reduce depressive symptoms, so you can choose which type you prefer.  Some studies suggest that aerobic and resistance exercises may be best, so try to include at least some time doing these.

Remember the most important thing is to start small and set goals that are achievable and sustainable.  Enjoy!

Posted in: Fundamentals