by Aaron Friday
Exercise exerts a very strong influence on our mental health, which determines in large part how much we enjoy living. It can make us happier, smarter, more relaxed, and more sociable. As Jack Lalanne said probably a thousand times, “Life is great when you’re in shape.” Indeed!
In the short term and long term, exercise:
- Improves mood and reduces anxiety
- Alleviates depression
- Improves cognition
In this short article, I’ll briefly explain how it works.
Improves Mood and Reduces Anxiety
Feeling great after a tough workout is a sought-after phenomenon. For a lot of us, feeling good is one of the strongest motivators to show up and put in the work day after day. Who doesn’t want to feel happy, empowered, alert, and relaxed?
Not surprisingly, exercise is an effective way to reduce stress and anxiety. Both the short-term symptoms of stress and anxiety (“fight or flight”) and the tendency to become anxious (i.e., perceive situations as threatening) are reduced by regular exercise.
Several mechanisms are responsible for this:
- Brain chemistry—Rigorous exercise triggers the release of beta endorphin, serotonin, and dopamine—chemicals that make us feel great and want to come back for more. This is probably how we get addicted to exercise (a good thing)! The effects of this brain-chemical release can last for hours afterward.
- Brain activation—Exercise stimulates activity in the left frontal cerebral cortex, which makes us happy, more confident, and more outgoing. The more we stimulate the left frontal cortex over time, the stronger it gets, and the more likely we are to have positive emotions most of the time.
- Heat—The body heat we generate during exercise makes us relax. As we get warmer, our body tries to restore its normal temperature by inducing relaxation. The motor nerves calm down, which leads to muscle relaxation, which then calms down the arousal center of the brain stem.
- Rhythm—Rhythmic movement leads to a “quieting” of cognitive activity (i.e., turning “off” our thinking), which reduces stress and enables us to relax.
All of these factors combine to make us feel great after a workout. In addition, exercise gives us a needed break from our other responsibilities, which reduces stress. It can also provide meaningful social interactions and a sense of empowerment or mastery, which are vital to our mental health.
The greatest benefits come after several months of regular exercise.
Exercise is considered just as effective as medication for treating clinical depression. In addition, the side effects of exercise are overwhelmingly positive—a fitter and better-looking body, and the reduction of disease risk (including the risk of dementia and Alzheimer’s disease).
Exercise fights depression via two mechanisms:
- Improved brain chemistry—Exercise elevates the levels of three neurotransmitters that are essential for mental health (and which are lowered during bouts of depression): serotonin, dopamine, and norepinephrine.
- Increased life satisfaction—Exercise increases one’s physical abilities, sense of accomplishment, and self-confidence. It can also provide regular, meaningful social interaction. As mentioned above, these things are vital to our mental health.
Improves and Preserves Cognition
Exercise improves cognition, which includes memory, analytical thinking, planning, focus, concentration, and decision making. Just as muscles are conditioned by exercise, so too is the central nervous system including the brain. Our brains get “in better shape,” so to speak, so we can resist fatigue better during sustained mental efforts.
Exercise also prevents cognitive decline due to aging. It slows down the aging of the brain through:
- Vascularization—Exercise preserves blood circulation in the brain and stimulates the formation of new blood vessels, so our brains get more oxygen.
- Tissue preservation—There is a positive relationship between aerobic capacity and brain density in the cerebral cortex, as well as better communication between brain regions.
In fact, physically fit people 55 and over do just as well on intellectually challenging tasks as young people, while sedentary people 55 and over tend to do much worse.
As if we needed more reasons to work out!