The Impact of Exercise on Mental Health

Frozen Fenway, 2017. @Brandon88Photo

Frozen Fenway, 2017. @Brandon88Photo

For those of you who know me, I’ve long viewed exercise as an essential part of my day. You could certainly classify it as an obsession of mine. From a young age, I have always used physical activity and athletics as a safe space to escape any negativity and focus my attention on activities I enjoyed most such as ice hockey, weight lifting, running, and swimming. As a youth hockey player, I remember the freedom I felt when I could put down my bookbag after a long day of school and simply focus my mind on hockey for a few hours.

Today, it’s very easy to tell when I haven't exercised; I feel tired, my productivity suffers and I’m simply not as fun to be around- just ask my girlfriend! However, on the days I have time to train, there is no better feeling than completing a hard met-con, spin class, or even just a long run. When I leave these workouts, I get more done, smile more, and sleep better.

While the impact of exercise on mental health and wellbeing is obvious to me, there are many people out there who struggle to start exercising or simply don’t see the point. For these reasons, I decided to write this article after taking a semi-deep dive into the research regarding the many benefits of different forms of exercise. While I certainly have left some things out (as I merely don’t have the time to list every single known benefit), I have tried my best to highlight some of the more interesting findings. I hope you find this article beneficial in adopting a sustainable exercise program that works best for you.


The Muscle-Brain Endocrine Loop-Exercise Helps Me Learn?

I’ll start with this finding, as it is the fascinating to me. We all know that exercise is beneficial for things such as maintaining muscle mass, burning through fat, and improving cardiorespiratory fitness, but did you know that the muscles communicate with the brain in a direct manner that can both improve memory and learning mechanisms AND decrease risk of depression? It’s true. During exercise, your muscles release small proteins called myokines. While there are many different forms of myokines, studies have shown that exercise-induced release of these factors may lead to:

1) Increased production of Brain-Deriver Neurotropic Factor (BDNF) in the hippocampus- BDNF plays a role in the growth, repair, and maintenance of our neurons (cells in our brain) and is important in the maintenance of neuroplasticity (the ability to learn novel things).

2) Increased formation of new blood vessels- In studies in rodents (often used to test hypothesis), exercise increased the production of VEGF (Vascular Endothelial Growth Factor). This increased production of VEGF led to increased production of new neurons and blood vessels.

3) Skeletal muscle activity may help regulate the sleep-wake cycle- Research has shown that a muscle-derived protein may be useful in regulating our circadian rhythms. So, if you’re having sleep trouble, perhaps some exercise is all you need!

*Note there are many more benefits listed here.

EXERCISE, SSRI’s, and BEHAVIORAL THERAPY- Which is best?!

If you’re someone who has ever suffered from a mental health disorder, you know that it’s very easy to turn to drugs, supplements, or even alcohol for relief. I told you how therapeutic exercise is for me, but does it compare to conventional treatments for mental health disorders such as depression? Let’s look at the research to confirm:

Review of the research on exercise and depression:

Summary:

  • This paper is a comprehensive review of the treatment available for depression and the current research of exercise as a treatment for depression. It is not a research study, rather it is a comprehensive review of the available research.

  • It started by introducing the pharmacological approach (usually SSRI’s) and mentioning that these treatments work for roughly half of the population, usually those suffering from more severe forms.

  • The paper then goes on to describe psychotherapies, such as cognitive behavioral therapy, which are shown to be fairly effective, especially when combined with other treatment modalities.

  • The paper then presents the case for exercise. The majority of the studies reviewed involved participants performing aerobic exercise, with a few resistance training studies mixed in.

Findings

  • One review of 850 individuals participating in randomized controlled trials showed aerobic exercise to reduce depressive scores by 7.5 points. However, the authors did not feel this was significant enough to confirm the benefits of exercise as a treatment modality.

  • In a separate review, researchers compared exercise to standard line of treatment (SSRI’s), placebo, or no treatment. In studies comparing exercise with no treatment or modalities such as cognitive behavioral therapy or pharmacotherapy, it was found that exercise leads to moderate clinical improvements in depressive symptoms.

  • The Duke Smile Studies- This is where things get a bit more interesting. This randomized controlled trial compared exercise, exercise + pharmacotherapy, and pharmacotherapy alone. I like this study because now we can work to really isolate exercise vs. pharmacotherapy. After 16 weeks of treatment, the groups showed no significant clinical difference in symptoms. HOWEVER, at 10-months follow up, those in the exercise group exhibited lower rates of relapse than both other groups and were 50% less likely to be depressed than the non-exercising groups!

Summing It All Up

After going through some of the research, there’s a few things I’ve learned:

1) Exercise is certainly beneficial to learning and memory (via BDNF and VEGF). The most studied modality is aerobic exercise, but there is evidence that HIIT and resistance training induce similar benefits.

2) For those suffering from clinical symptoms of major depression, the best treatment seems to be a mixture of pharmacological therapy, behavioral therapy and exercise prescription.

3) While exercise may not outperform other modalities to a significant degree when examined during randomized controlled trials, it certainly appears that it is the single most effective modality for treating the long-term symptoms associated with depression.

4) Adhering to an exercise program is the best way to prevent relapse of symptoms.

I tried my best to look over the data with as little bias as possible (which is difficult since I just wanted to confirm the benefits of exercise). After doing so, I am convinced that exercise of all forms is protective over our mental health. My reasoning for this (in addition to the points outlined above) is there are also social and behavioral factors at play. Some of my closest friends, mentors, and competitors are those I’ve met through athletics and there is something to be said about the social connection that comes with exercise. I hope you find this information interesting and helpful in optimizing your health and wellbeing!