Aerobic exercise — has a significant, beneficial impact on the brain.

I found that exercise in nature, like hiking in the woods or doing yard work, is especially helpful.

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Erin Brodwin
Business Insider
October 4, 2017

Want an all-natural way to lift your mood, improve your memory, and protect your brain against age-related cognitive decline?

Get moving.

A wealth of recentresearch, including a new study published this month, suggests that any type of exercise that raises your heart rate and gets you moving and sweating for a sustained period of time — known as aerobic exercise — has a significant, beneficial impact on the brain.

"Aerobic exercise is the key for your head, just as it is for your heart," said an article in the Harvard Medical School blog "Mind and Mood."

Most research suggests that the best type of aerobic exercise for your mind is anything you can do regularly and consistently for 30-45 minutes at a time. But the latest study suggests that any kind of workout — whether it's for 5 minutes or 45 — can have beneficial impacts on mental health.

The new study, published in the American Journal of Psychiatry, is the largest long-term study of its kind to look at the link between exercise and mental health, with a special focus on depression.

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The results suggested that as little as one hour of exercise each week helped shield people against depressive episodes. Notably, that exercise did not need to be aerobic — even participants who got moving without becoming breathless (perhaps with an activity like a long, moderately-paced walk) were significantly less likely to report symptoms of depression compared with those who did no exercise.

Plenty of other research has revealed a powerful connection between mental and physical fitness across varying levels of intensity. Some benefits — like a lift in mood — can emerge as soon as a few minutes into a sweaty endeavor, while others — like improved memory — might take several weeks to crop up.

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A pilot study in people with severe depression, for example, found that just 30 minutes of treadmill walking for 10 consecutive days was "sufficient to produce a clinically relevant and statistically significant reduction in depression." Aerobic workouts appear to help reduce levels of the body's natural stress hormones, such as adrenaline and cortisol, according to a recent study in the Journal of Physical Therapy Science.

In older people, the best way to protect against age-related brain decline seems to be aerobic workouts. A study published in May found that in adults aged 60-88, walking for 30 minutes four days a week for 12 weeks appeared to strengthen connectivity in a region of the brain where weakened connections have been linked with memory loss. And a study in older women who displayed symptoms of dementia found that sweaty, heart-pumping exercise was linked with an increase in the size of the hippocampus, a brain area involved in learning and memory.

Several studies even suggest that aerobic workouts provide the best protection against other types of cognitive decline, too. A study involving hundreds of breast cancer survivors concluded that such exercise seemed to reduce the symptoms of "chemo brain," a commonly reported side effect of cancer treatment that involves memory loss and difficulty focusing.