They say age is just a number. But some days we all wish that number was lower.

Humans have been exploring ways to slow down or even reverse aging for thousands of years. It’s only natural … our mortality reveals itself to us on a regular basis.

But what if you could be four years younger with minimal cost and effort? A new brain study reveals that this is possible, in a way.

According to a new study, engaging in everyday physical tasks like walking the dog and taking out the trash can give a healthy boost to our brain’s processing speed.

The study participants’ cognitive processing speed, the speed at which our brains receive and process information, was on par with a person four years younger on the days they engaged in physical activity. Researchers found the same positive results whether participants went for a short walk or an intense jog.

Researchers said the study did not show enhancements to working memory, the ability to retain and analyze information, but the response time on working memory tasks improved.

While the study reveals the positive short-term effects of physical activity, it did not measure improvements over time, something future studies may explore.

Ultimately, researchers say the study shows the important role that movement plays in our brain health, even if it’s through small, everyday tasks.

Walk the dog, mow the lawn, take out the trash — these activities may not quite be as exciting as stumbling across a flowing fountain of youth, but they still give our brains a healthy boost.

Age may be just a number, but if we can reverse that number just a little bit, why not?