New Study Suggests Remaining Sedentary May Shrink Your Brain

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We already have plenty of good reasons to exercise. Regular movement has been shown to help create a stronger body, a healthier heart, and a calmer mind. But recent research has revealed yet another reason to get off that couch and get moving: a bigger, healthier brain.

The new study, published in the journal Neurology, found that people who were sedentary during midlife had smaller brains later in life compared to their fitter peers. Although the amount of brain shrinkage was small, it was substantial enough to increase the less fit participants’ risk of dementia and memory loss.

The study

The study used data compiled by the Framingham Heart Study, which has collected data from thousands of people over a nearly 70-year time span. Researchers examined data from over 1,500 participants who took a treadmill test and got an MRI scan when they were about 40 years old. Twenty years later, the same participants did a similar treadmill test and got another MRI scan.

The treadmill test measured the amount of time participants could run on the treadmill before their heart rate reached 85 percent of their estimated maximum heart rate. This time was used to estimate the participants’ peak VO2. This is the maximum amount of oxygen one’s body can use in one minute. The study showed that the less efficiently a participant could use oxygen, the more age-related brain shrinkage they showed two decades later. The study further demonstrated that participants with a greater increase in heart rate and higher blood pressure during the treadmill test were also more likely to have smaller brain volumes later in life.

Lead researcher Nicole Spartano, a postdoctoral fellow at the Boston University School of Medicine, summarized the results in a press release: “We found a direct correlation in our study between poor fitness and brain volume decades later, which indicates accelerated brain aging.” However, she also noted that the study does not prove that poor physical fitness causes a loss of brain volume; instead, it shows an association between the two.

Exercise and your brain

Although research has yet to prove causation, a growing body of evidence suggests a strong connection between exercise and brain health. We recently reported on a study that suggests women with stronger legs may also have a healthier brain.  A 2014 study demonstrated that seniors who exercised three times per week for 12 weeks showed greater memory skills as well as increased blood flow in the brain. And a 2010 study, also of seniors, found that walking around a track three days per week for a year appeared to increase the size of the hippocampus in participants.

This research indicates that the brain continues to be malleable even later in life. So even if you’ve never exercised before, these studies suggest that older age does not mean it’s too late to reap the benefits of more movement.

Starting to exercise

If you are completely new to exercise, or returning after a long hiatus, here are three important tips to keep in mind:

Start with low-impact exercises

Low-impact exercises, for example, using an elliptical machine, going for a swim, and going for short walks, put minimal stress on your joints. Practicing mind/body exercises such as yoga and tai chi are also gentle, calming, and low-impact ways to start incorporating more movement in your life. Once your limbs and joints have gotten used to the new pressures you’re putting on them, you can try transitioning to higher impact exercises such as jogging.

Go slow

Jumping in too fast can result in pain and injury, which can lead to becoming unmotivated. Try to take it slow; don’t put too much pressure on yourself at the beginning. You don’t even need to exercise every day. Remember, the participants in one of the above-mentioned studies saw healthier brains after exercising only three days per week.

Make a schedule and stick to it

Your primary goal when you begin exercising should simply be to do it. The easiest way to meet this goal is to set a schedule and stick to it. You don’t skip your work or family obligations that are on your calendar, so consider your exercise obligations to be just as important!

What do you do to keep your brain healthy?