A Fitness First For Women

(CBS)  For the first time, researchers have determined how much a woman really needs to exercise to stay as fit as possible for her age.

The Early Show medical correspondent Dr. Emily Senay explained to co-anchor Harry Smith the benchmarks are new because, "All the studies until now have looked at men. So this is the first time that we can honestly say exactly what exercise capacity a woman needs to have at a specific age to be healthy."

Senay says the researchers took about 10,000 women and looked at two different groups, one consisting of healthy women and the other, women who'd been referred because they had some suggestion of heart disease or actually had heart disease.

They took stress tests, the classic protocol doctors go by to see how effectively a heart is working.

The researchers were able to develop a chart from that. "It showed something very important," Senay observes. "It showed that women who exercised at less than 85 percent capacity for that specific age group were actually two times more like to develop heart disease and two times more likely to experience death.

"We've seen similar things in men, that show this can really be very predictive of your overall health. So now we have a chart that works for women for the first time.

"And it's not exactly the same as the one that's in men."

So how much do women need to exercise to literally make a difference in their health?

"That's where it gets tricky," Senay points out. "It's not exactly how much you need to exercise. The chart tells you how fit you need to be at a specific age level and for your gender, for women. So it's something that [women] probably have seen when [they] go into the gym and look at those things on the bicycles or the treadmills. And it's called a met, a metabolic equivalent. That's the value that the researchers used.

"[Women] probably don't need to worry about that yet, because they need to reprogram a lot of these things to include charts that are appropriate for women. But what they're saying is that this allows doctors and hopefully, in the future, women the chance to have a more accurate picture of exactly what fitness level they need to be at to protect their health."

It goes even further, Senay notes: "A lot of people say this should be included in an overall assessment of a person's health, just as we would check their blood pressure or just as we would check their cholesterol level. We're not there yet. But it's something for the future."