Move. Dammit.

Say the folks at the National Institutes of Health: “People who exercise not only live longer; they live better.”

The MacArthur Foundation Study of Successful Aging, a ground-breaking, myth-exploding ten-year project that revolutionized the study of gerontology, concludes by touting the “powerful effects” of exercise and calling it “the only anti-aging regimen that actually works.”

The renown scientists who head the USDA Human Nutrition Research Center on Aging at Tufts University believe that, besides quitting smoking, “there is no single thing that will increase vitality at any age other than exercise.”

One of the major conclusions of the Nurses Health Study, among the largest (more than a quarter of a million women) and longest-running (almost forty years) investigations of factors affecting women’s health? “Higher levels of midlife physical activity are associated with exceptional health status…”

An eight-decade-long investigation of 1500 Californians found that being active in mid-life was the single most important predictor of good health.

Reviewing more than forty studies on the benefits of exercise, researchers writing in the International Journal of Clinical Practice concluded that regular exercise helps prevent more than 25 diseases and health conditions later in life. Among them are the diseases that rob us of vitality and youth — not to mention years: heart disease, diabetes, high blood pressure.

So really…you need another reason to get up and move?

Okay, here it is – and it’s doozy:

Adults who exercise can halt or reverse “natural” “age-related” shrinkage of the brain. Exercise promotes more gray matter in the hippocampus region, which correlates with improved cognitive abilities and memory.

Notice that I placed quotes around natural and age-related because it appears that brain shrinkage is neither. While it’s true that that the hippocampus typically declines in volume at a rate of about 1 to 2% each year after age 40, if regular aerobic activity can, as the researchers found, “provide a significant protective effect that can eliminate or even reverse this shrinkage,” then – hold on – shrinkage is not natural. Or even age-related. It is, in fact, the cumulative result of inactivity, the effect of lack of vigorous blood flow to the brain, the effect not of the years going by but of the years going by on the couch. Remember, when you ask the heart to pump more blood faster, as you do in exercise, the blood travels everywhere. Your brain is bathed in the good stuff – that’s the scientific term – just like your muscles are.

Here’s what the recent study I’m talking about concluded: “After controlling for age, gender, and total brain volume, total minutes of weekly exercise correlated significantly with volume of the right hippocampus.”

There are many parts of us we don’t want to get bigger as we age, but the brain ain’t one of them.