Diana Swain:

Here's some extra motivation for you the next time you try to push yourself to go to the gym. A new study has drawn a direct line between exercise and mental agility as we all age. Caroline Dunn has these details.

Caroline Dunn:

At 67, Myrna McRoberts is confident her active lifestyle is keeping her body healthy.

Myrna: "I knew I could ride a bike, and I thought I had good blood, but I didn't know if I'd be able to put square pegs in round holes."

So she jumped at the chance to take part in a study that measured the relationship between staying active and staying mentally alert.

The blind study compared a group of healthy but inactive women with healthy and active women.

Myrna: "I know I feel more alert when I'm exercising."

The study found the group of active women had a resting blood-pressure that was 10% lower than the inactive group.

When exercising, those active women had a 5% better blood flow in their brains.

Exercise boosts cognitive skills by 10%.

And then they scored 10% higher on cognitive skills tests.

Marc Poulin, University of Calgary: "We looked at things like memory, things like complex thinking, multitasking and things like that. Those women that were fit or active had better on cognitive outcome scores than the women who were sedentary."

That's importance, because incidents of dementia could double over the next quarter-century, as the "Baby-Boomer" generation becomes the elderly generation.

Study participants like Merceda Schmidt offer hope to all of us. She's an active 91 year-old who walks 6 kilometers a day and she's as sharp as a tack.

Merceda: "It teaches me a great deal. I never realized the interplay there is between the two. It just happened that that was the way I was born, my legs always wanted to go.

Now knowing there is a relationship between those legs and her mind is encouraging her to keep moving.

Merceda: "If I want to live a happy end of my life, a golden age, I have to work at it. And it isn't really work, you enjoy it. It lifts your spirit."

The bottom line, say researchers, regular exercise is a healthy thing for an aging body, and it turns out, an aging mind, too.

Caroline Dunn, CBC News, Calgary.

EXERCISE & DEMENTIA - ARTICLES ON THIS SITE:

VIDEO + TRANSCRIPT University of Kansas experts show cardio-respiratory fitness appears to make a big difference in the early stages of Alzheimer's.

A recent study shows that regular walking protects the aging brain.

Even moderate exercise helps ward off Alzheimer's and dementia.

40 years of research shows that regular physical activity can help prevent dementias such as Alzheimer's.

SOURCE:

CBC News, Calgary, Canada

Week of April 5 - April 12, 2009