The number one strategy for keeping your brain young is physical activity. Luckily, you don’t have to become a triathlete to live longer — just 20 minutes of daily brisk walking will lower your risk for Alzheimer’s disease.

Exercise boosts endorphins, which lift mood. Working out also produces a protein called brain derived neurotrophic factor (BDNF), which stimulates brain cells to sprout new branches and therefore communicate more effectively with each other. In fact, regular physical exercise will actually make your brain bigger — and a bigger brain is a better brain.

One large-scale study of more than 16,000 Harvard alumni showed that those who followed a regular exercise routine enjoyed at least a couple of years of longer life expectancy. And death rates for men who played tennis, swam, jogged, or took brisk walks were about a third lower than the sedentary volunteers.

In fact, people who engage in almost any sport or physical activity that gets the heart pumping oxygen and nutrients throughout the body and brain have a lower risk for cognitive decline and longer life expectancy.