We all know that exercise and physical activity are helpful in maintaining good physical health (I hope!) We know that exercise builds muscle, and increases fitness, and generally can make life a little easier. That makes sense – you use your muscles, heart, and lungs when you exercise, and they get stronger to keep up with the demands of your workout.
You might also know that exercise is good for your mental health. Maybe you heard that it’s a primary treatment recommendation for depression, or just heard a friend describe getting a mental boost from a workout. But since most people aren’t doing mental calculus while they work out, where does that boost come from?
Our short term feel-goods, as it turns out, come in part from the brain itself. During times of stress, which is how the body perceives exercise, the brain releases endorphins – those hormone things everyone has heard of. These chemicals help block pain signals that the stress might be causing – kind of a preventative measure. These endorphins also create feelings of euphoria (they are chemically similar to morphine!) and can increase positive thoughts and feelings. Since this provides both an immediate and (with regualr exercise) lasting effect, exercise is a particularly useful aspect of treatment for depression, anxiety, and other mental illnesses.
Endorphins, it turns out, are not the only players in the exercise-and-brain game. During times of stress, the brain releases another chemical, brain derived neurotrophic factor (BDNF), which serves to protect the brain cells and their connections with each other, called synapes. BDNF helps improve cell signaling and can reverse cell degradation. Improved connections between brain circuits mean improved memory, attention span, and processing speed. In some studies, increased levels of BDNF have actually been shown to have a reparative effect, and may restore learning abilities and memory. These improvements have been shown to occur even with modest exercise, like going for a daily walk.
The neuroprotective effects of BDNF can have a some life-long benefits. Numerous studies of older adults have shown that those who were more physically active earlier in life were less likely to develop degenerative brain diseases such as Alzheimer’s disease or dementia. People in the early stages of these diseases also benefit from exercise and physical activity – the aforementioned walk can be helpful in preventing disease progression. BDNF production does tend to decrease as we age, so since we can all benefit from the chemical boost that exercise provides, getting started with an exercise program will be beneficial regards of age or mental health.
Chemicals aside, exercise actually benefits the brain in some of the same ways that it benefits the rest of our body. The arteries in our brains are very small, but still susceptible to the same blockages as any other artery in our bodies. Tiny blockages can lead to potentially unnoticeable ministrokes that damage tiny areas of the brain and potentially leading to long term decline mental health. Fortunately, these arteries are also positively affected by exercise – the same way as the rest of our blood vessels. Good blood vessel health also means optimal blood flow to the brain, and with it, optimal delivery of nutrients to the brain. Consider the fact that the brain is by far the largest user of blood sugar in our bodies. Sounds like a good idea to keep those channels open, right?
Take home message: Exercise is good for more than just your muscles, heart, and lungs, and the buzz you get after a workout or a walk may just be your best defense against mental illness, at any age!