Perhaps you have a rough idea about how exercise affects your health, weight, and energy levels. But do you know about its impact on the brain?
The neurobiological benefits of exercise are clear and significant and can explain why exercise can improve cognitive functioning, mental health, and memory, and also hinder the development of certain neurological conditions.
In an article entitled Exercise is Brain Food (2008),1 Ploughman presents several dominant neuroscientific theories that explain how physical activity positively impacts brain health:
While exercising, oxygen saturation and angiogenesis (the formation of new blood vessels) occurin areas of the brain associated with rational thinking, as well as social, physical and intellectual performance. It is thought that the processes involved here are similar to the way exercise influences the cardiovascular system;
Similar to common medications for anxiety and mood disorders, exercise can regulate the production and release of neurotransmitters like serotonin, dopamine, and norepinephrine, which are known to play key roles in areas of the brain that are involved in emotional processing;
Exercise can also reduce levels of stress hormones, which are generally elevated among people with mental health problems such as depression. Like other stressors, exercise activates the body’s stress response system which, over time, can lead to positive adaptations in the body’s ability to regulate its stress response;
Exercise can support neurogenesis, which is the process of generating new neurons in the brain. Among humans, there is growing evidence to show that aerobic exercise can have a positive effect on the volume of the hippocampus (an important part of the brain involved in emotional processing).
This is particularly interesting because people with depression typically display reduced hippocampal volume.
Of course, the mental health benefits of exercise are not all physical, and there are several psychological mechanisms that may explain some of the mood-boosting effects of exercise.
For example:
The time-out hypothesis proposes that exercise offers a distraction from your day to day worries and concerns;2
Evidence supports that people with poor mental health show a bias in attention toward certain negative stimuli and interpret common events negatively.
Exercise can help to attenuate this response, and shift your focus to more positive stimuli;3
Finally, exercise can help you feel better simply because you expect to feel better. Up to 50% of the mood-enhancing effect of exercise may be down to this phenomenon, although the effects and benefits are no less real.4
These are the most common theories as to how exercise can improve your mood and brain health. But, for the moment, they are just theories, and really the full effects of exercise are yet to be fully understood, and it is likely that exercise acts through a complex combination of these proposed mechanisms.
Nonetheless, although the mechanisms remain to be fully understood, there is an overwhelming amount of evidence to support the mental, as well as physical, benefits of being active!
Read more articles in our Cognitive Function and Exercise series
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