Regular physical activity is an important part of a healthy lifestyle. Exercise is not only good for your muscles and bones but also an essential part of keeping your brain healthy.
Over time, physically active people tend to have less cognitive decline than their sedentary counterparts.
However, physical activity does not just improve brain health in older adults – it also benefits the brains of younger people. Here we will look at some of the effects physical exercise has on the brain throughout its lifespan.
Physical activity causes many physiological changes in the body, contributing to improved mental function (e.g., the release of neurotrophins like BDNF).
But what about specific changes within the brain? With animal studies, researchers can examine these microscopic changes by looking at gene expression patterns or cell structures, but this is more difficult with human populations.
So far, studies have indicated that regular exercise during young adulthood may be especially important for preventing cognitive decline as we age.
Some of the most interesting research on exercise and the brain has come from animal studies. For example, one study found that mice who ran regularly had more new neurons in their hippocampus (a memory centre) than those that were sedentary after several weeks.
Other studies show increased hippocampal connectivity and neurogenesis in exercise animals compared to sedentary animals.
More recent studies have shown that physical exercise can increase hippocampal volume and improve memory function. Exercise also increases the production of nerve growth factors (NGF) that are important for maintaining neuron health. These structural changes in the brain may account for some of the effects of exercise on cognition.
Exercise can also have positive effects on mental health by relieving stress, reducing anxiety, and alleviating depression in some cases. Furthermore, regular physical activity tends to improve attentional performance. This may be because it decreases fatigue or allows for more efficient neuronal processing in the neurons responsible for maintaining attention. Exercise may also enhance sustained attention by increasing lasting arousal and vigilance.
In terms of effects on the brain in childhood, several studies have suggested that exercise may decrease some types of aggressive behaviour in boys who are at risk for this type of behaviour. In addition, research shows that children with poor motor skills tend to perform worse academically than their more skilled peers. With early intervention, however, exercise can improve motor function in children and may be an important factor for academic success later on.
Significant research has focused on how physical activity affects older adults, as there is a growing number of people over the age of 65, and cognitive decline becomes more common as we age.
Research suggests that regular aerobic exercise seems to positively impact cognition, memory, and mood in older adults.
Physical activity may help to reduce the risk of Alzheimer’s disease by improving cognitive performance, increasing brain volume in regions that are impaired early in the disease process (e.g., grey matter), and decreasing amyloid beta accumulation – an indicator of Alzheimer’s.
Regular exercise can also improve symptoms of neurodegenerative disorders, such as Parkinson’s disease. For example, research shows that the neurotrophin BDNF is released during short bouts of exercise and may help to protect dopamine neurons from degeneration in Parkinson’s patients.
Moreover, some research suggests that physical activity increases neurotransmitter levels involved in the brain’s reward and pleasure centres; this may be beneficial for Parkinson’s patients, who usually have decreased levels of these chemicals.
Regarding mental illness, research has found that physical activity can improve cognitive function in schizophrenic patients. Mice with schizophrenia also show improvements in their symptoms after exercise training.
However, there is no solid evidence for disorders such as autism and depression to support the notion that exercise offers any cognitive benefits.