Healthy Body, Healthy Mind?: The Antidepressant Effects of Exercise

Mariam Elnazali

     Mental illness affects us all: whether that is something we personally struggle with, or it’s someone we know, like a family member or a friend. Sadly, mental illness is an issue that is becoming increasingly common. One of the most prevalent, depression has become the number one reason for disability, impacting approximately 3,000,000 people. It is even linked with a number of physical illnesses such as cardiovascular diseases. The problem of high mental illness rates aren’t only something that affects people on a personal level, it also has heavy economic impacts on our societies. While there have been many strides in improvements for treating depressive treatments, in psychotherapy and pharmacotherapy (drug treatments), much of the research suggests the treatment effects of these treatments leave room for improvements. Little or moderate effects have been found using these treatments, and the even bigger issue is that the prevalence of illness rates in our populations hasn’t really been affected.

A major issue with the treatment of depression is that different people have different symptoms, no two are alike. While the current treatments certainly need some work, evidence has indicated that physical activity acts as an antidepressant, proposing a complementary type of treatment alongside these current ones. Exercise has numerous benefits for our body, both physically and emotionally. We have all heard about the positive benefits of physical activity on our mental health, "Healthy body, healthy mind" we are told. The current literature on physical activity and its effects on depression suggests lowered rates of depression as a result of high rates of exercise, with 17% less of a chance compared to individuals with less frequent exercise habits. As well, research has found links between low physical activity and the chance of depression.

But our understanding behind these effects is still limited. Researchers are only starting to understand the mechanisms behind this idea of using exercise for the treatment of depression. Exercise offers a potentially novel method to help in alleviating the symptoms of depression and reducing the risk of the illness to begin with. However, to optimally utilize this as a treatment, we need to understand how it works. 

A review conducted by Kandola, Ashdown-Franks, Hendrikse and Sabiston looked at these processes, and the effects that exercise has on the brain, such as inflammation of the brain, on stress and self-esteem, and many other changes. For example, they suggested that targeting these neuroplasticity pathways might help to counteract the brain structure abnormalities that have been found in people with depression. Abnormalities, such as a smaller hippocampus compared to depression-free individuals. This might potentially help reduce depressive symptoms, if this disruption of pathways contributes to depression, as it has been theorized. You're asking me though, what is neuroplasticity? Basically, it's the brain's ability to change itself after new events such as a brain injury or a disease by forming new connections. They discussed how different intensities for exercise (for example, high intensity vs. less intensive) can produce different neural and biological responses, and how exercise times would vary depending on the individual.

Further research on these underlying mechanisms definitely needs to be done to optimally deduce the best applications of exercise to help in treating depression. The benefits resulting from this would be to potentially apply exercise treatments for depressive symptoms, which could help to lower the prevalence in illness rates, if found to be successful. Or, it could help to reduce the percentage of people who rely on psychotherapy and pharmacotherapy. The potential for new treatments in this area of mental illness is certainly exciting. Meanwhile, the research about the positive impacts of physical activity on depressive symptoms is enough to warrant hitting the gym if suffering from a mental illness such as depression. It's good for your body, so either way, incorporating a little exercise into your lifestyle is a win-win!

References:

Jr., W. C. S. (2017, January 24). Definition of Neuroplasticity. Retrieved from https://www.medicinenet.com/script/main/art.asp?articlekey=40362

Kandola, A., Ashdown-Franks, G., Hendrikse, J., Sabiston, C. M., & Stubbs, B. (2019). Physical activity and depression: Towards understanding the antidepressant mechanisms of physical activity. Neuroscience and Biobehavioral Reviews, 107, 525-539. doi:http://dx.doi.org.proxy1.lib.uwo.ca/10.1016/j.neubiorev.2019.09.040