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HealthInfo Canterbury

How exercise helps depression

FDP couple walkingWe all know exercise makes us feel better, but most of us have no idea why. We assume the exercise is burning off stress or boosting endorphins. But, the real reason we feel so good when we get our blood pumping, is that it makes our brains function at their best. That is the real benefit of exercise.

Building muscle, conditioning the heart and lungs, and so on, are important, but they are really side effects. The real point of exercise is to build and condition the brain.

In today's technology-driven world, it is easy to forget that humans are born to move. In the past we had to survive as hunter-gathers. So the link between food, physical activity and learning is built-in to our brain. But we no longer hunt and gather, and that is a problem.

The inactive nature of modern life is one of the biggest threats to our wellbeing. The evidence is everywhere. Sixty-five percent of New Zealand adults (aged 15 and over) are overweight or obese. Thirty-three percent of children (aged 2 to 14) are overweight or obese. Over 5% of the population has diabetes. What is even more disturbing, and what no one recognises, is that we are killing our brains, physically shrinking them.

To keep our brains at full performance we need to work hard. Physical activity is crucial to the way we think and feel. Exercise improves mood, reduces anxiety and increases attention. It guards against stress and reverses some of the effects of ageing in the brain. In women it can reduce the effect of hormonal changes.

Exercise increases levels of serotonin, norepinephrine and dopamine. These are important neurotransmitters (chemicals in the brain) that control your thoughts and emotions. A lack of serotonin causes depression. Stress increases hormone levels, which damages nerve cell connections. Chronic depression shrinks parts of the brain. On the other hand, exercise can reverse this process and strengthen the brain. The brain responds like a muscle, growing with use and shrinking with disuse.

Understanding the role physical activity has on your brain will motivate you to include it in your life in a positive way. Things do not work the same when you are forced to exercise. It is exercise you want to do that really counts.

Written by HealthInfo clinical advisers. Last reviewed April 2018.


See also:

Green Prescription

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Page reference: 126744

Review key: HIDEP-48681