Mental calisthenics – whether it's crossword puzzles, word search or the brain training games websites like Lumosity advertise – are touted as a great way to stay sharp. As it turns out, physical activity is just as important — probably more so — in maintaining brain health. A new study from the Cooper Institute in Dallas has found that keeping fit can ward off dementia. Nearly 20,000 adults were followed for 24 years. The people in the highest 20 percent of the group for fitness at midlife had 36% reduced risk of dementia over the folks in the lowest 20% for fitness. That's huge.
The new findings are important but they aren't groundbreaking – they build on a solid, significant body of research showing that if you exercise your body, you exercise your brain too. Another recent study, at the Beckman Institute for Advanced Science and Technology at the University of Illinois, found that mice with a running wheel in their cage had healthier brains and scored higher on cognitive ability tests than other mice that didn't — even if the other mice had a toy-rich environment. The scientists could actually see differences in the structure of the various mouse brains.
It makes sense that the increased blood flow through brain tissues during exercise could help keep it young and vital. It turns out that exercise acts at a far more primal level too, actually slowing down the aging process. The DNA in our cells is protected at the end of each strand by little caps (think of the hard plastic tips on shoe laces) called telomeres. As we age, the telomeres begin to break down, exposing our DNA to damage. Exercise is one of the few proven ways to keep the telomeres stronger longer.
In addition, exercise stimulates the brain to produce new cells. For a long time, it was believed that we never had any more brain cells than we were born with – from there it was a slow, steady march downward as cells died off. But research has discovered that our brains can and do generate new cells, and one of the few things that stimulates this sort of brain growth is — you guessed it — exercise.
The benefits of exercise for brain health are undeniable, but the best way to use your body to exercise your brain isn't yet clear. Most of the studies to date have involved some type of cardio exercise, though at least one saw cognitive improvement after a sustained program of weight lifting. I think it's safe to say that while we may eventually discover that a certain type of exercise packs the biggest punch, anything you do is a plus for your brain.
So walk, hike, bike, take a yoga class or play a set of tennis or a round of golf. I missed out on the dancing gene, and I always think I get a double benefit for my brain from Zumba because my brain has to work so hard to follow the class.