How Exercise Offers Relief from Depression

A review of “73 randomized controlled trials that included about 5,000 people with depression,” published by the Cochrane collaboration, concluded that exercise was as beneficial as medicinal or psychological therapies in the treatment of depression. The review can be found at this link: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004366.pub7/full. Unfortunately, that article is hidden behind a paywall, so I could not read the original article. Instead, I first learned about this study by listening to the National Public Radio (NPR) and subsequently looked an article they wrote about the review, linked here: https://www.npr.org/2026/01/12/nx-s1-5667599/exercise-is-as-effective-as-medication-in-treating-depression-study-finds.  

The NPR article explains that “Exercise can help improve neurotransmitter function, like serotonin as well as dopamine and endorphins. So there is certainly overlap between exercise and how antidepressants offer relief". I have recently been working out after work and can attest to the benefits of exercise for my mental well-being. If you want to read a general overview of the benefits of exercise for depression, I recommend you to check out NPR’s article. In this article I will focus on the neuroscience referenced in the article, specifically about the neurotransmitters and growth factors and what they do to the brain.  

AI depiction of a neuron

Serotonin 

Serotonin is known as a natural mood stabilizer, the feel-good chemical, but there is more to it than just making us feel good. Only 10% of serotonin released acts as a mood stabilizer, being released in the brainstem, while 90% of serotonin is released in our intestines (https://my.clevelandclinic.org/health/articles/22572-serotonin). Serotonin does much more than just stabilize our mood, its most important effect is in the gut where it speeds up digestion to get rid of irritating food, it helps you stop feeling hungry when you are actively eating, it can also cause nausea if too much serotonin is released in the gut than can be digested, helps you sleep, it is secreted by platelets to increase wound healing, and can play a part in determining the density of our bones. If you have a low level of serotonin, you may feel depressed, anxiety and have trouble sleeping. All in all, it is quite an important neurotransmitter, but it works in conjunction with other neurotransmitters, such as dopamine and endorphins.

Dopamine

Dopamine is known as another feel-good chemical. It is part of your body’s reward system, released when you are doing things you need to do to survive, or what your body thinks it needs to survive (https://my.clevelandclinic.org/health/articles/22581-dopamine).  When you are doing something that is pleasurable your body secretes dopamine, which can, unfortunately, play a part in addictive behaviors. When you have the right level of dopamine you feel happy, motivated, alert, and focused. Low dopamine levels are associated with ADHD, Depression, Parkinson's Disease, and restless leg syndrome.

Endorphins 

Endorphins are secreted by the hypothalamus. They are released when the body experiences pain or stress (https://my.clevelandclinic.org/health/body/23040-endorphins). Endorphins are the body’s natural pain-relieving chemical, literally turning off pain. They elicit a stronger effect on the body than morphine. Endorphins, when released, attach to the reward centers of your brain, which triggers the release of dopamine. They are commonly released during exercise. Endorphins have been shown to reduce the effects of depression, help with anxiety, improve self-image, and regulate appetite, thus helping with weight loss.

Brain-Derived Neurotrophic Factor

In addition to releasing beneficial amounts of these neurotransmitters exercise also stimulates the release of a brain specific growth factor, brain-derived neurotrophic factor (BDNF). BDNF promotes the growth of new neurons and an increase in neuronal connections called synapses (https://taylorandfrancis.com/knowledge/Engineering_and_technology/Biomedical_engineering/BDNF/).  More neurons or connections means better learning and neuronal plasticity. This is hugely beneficial as people who are depressed often have difficulty learning, so a higher release of BDNF would greatly aid this problem.

Benefits of Exercise

Exercise, it turns out, can not only help us lose weight and gain muscle, but it can also help prevent or treat depression. It stimulates the release of a host of beneficial neurotransmitters which help induce the feeling of happiness and contentment, as well as increasing the release of beneficial brain specific growth factors that help with learning and memory. So, get out there and go for a run, lift some weights or learn some martial arts. It will literally build your body and your mind.