Not that I needed any convincing, but a couple of recent studies should have those of us who like to lace up expensive footwear, throw on layers of clothing and face winds that can freeze exposed flesh in minutes just so we can burn enough calories to eat an extra cookie or two, feeling pretty good.

Nothing to sneeze at, these scholarly reports either. One of them brought a special glow to my eyes – a variation of the use it or lose it theory.

Researchers at Yale University studied 415,000 runners in the New York City Marathon over a 16-year period – from 1983-1999. The study suggests that runners over the age of 50 improve their performance more quickly than younger runners. And women fare better than the men.

The study found that as a group, 50-59 year old women sliced two minutes off their time each year in the study period. Men shaved 8 seconds off their time per year.

One of the lead researchers on the team says the study shows people can maintain a very high performance standard into their sixth or seventh decade of life.

Milton, Ontario's Ed Whitlock is living proof of that. At 73, he slashed five minutes off his own world record for fastest marathon for a person over the age of 70. He lowered that mark to two hours and 54 minutes in Toronto in September. With a time like that, he'd be picking up hardware even if he were 20 years younger.

The researchers go on to say their study reinforces the notion that older people grow weaker not just because they are getting older, but because they’re not using their muscles as much as they did when they were younger.

The good news: you don't have to be a marathoner to see the benefits of exercise past 50. Regular workouts, the researchers point out, will reduce cholesterol, blood sugar and blood pressure, keep your weight down and improve your mental outlook.

Reassuring words, especially for those of us sliding into that second half century of life.

The other big study came out earlier this month in the prestigious science journal Nature. Born to Run, it was called. University of Utah biology Prof. Dennis Bramble and Harvard University anthropology Prof. Daniel Lieberman argue that it's running – especially the long distance endurance stuff – that separates us from the apes, what makes us human.

The scientists theorize we evolved from ape-like creatures to the way we look today because of the need to cover long distances and compete for food. Humans developed the ability to run so we could get to those fresh carcasses the buzzards were circling quicker than other animals.

Bramble and Lieberman studied more than two dozen traits that increase humans' ability to run. Among the things that make us different from the apes are longer legs to take longer strides, shorter forearms which help the upper body counterbalance the lower half during running and larger disks which allow for better shock absorption.

Another key feature: big buttocks. Well, relatively big.

Bramble says human buttocks are muscles critical for stabilization in running because they connect the femur – the large bone in each upper leg – to the trunk. People lean forward when they run. That butt of yours keeps you from falling on your face each time your foot hits the ground.

Next time you’re at the zoo, check out an ape's ass. Not much there. Won't see him running too far.

Evolution made us runners – at any age. Still, apparently 70 million Americans refuse to believe in evolution.

I think they're called golfers.