By Neal Templin

Sitting takes a toll on our health. You can reverse the effects with exercise — a lot of it.

If you sit eight hours a day, it takes 13,000 steps a day to completely offset the effects, Dr. William Kraus, a cardiologist at Duke University, told Barron's.

"We have to pay a price for sitting eight hours a day," he said. "It isn't a gimme."

Kraus, who advised the federal government's Centers for Disease Control and Prevention on its fitness guidelines, follows his own advice. Every day, he runs or walks 13,000 steps.

In fact, he talked to Barron's while he was walking about.

That big number really is how much it takes to "overcome sitting eight hours a day, which most of us do, if we're being honest," Kraus says.

Why is sitting so bad for us? "We think it has to do with the metabolic toxicity associated with the lack of exercise," says Dr. David Alter, a cardiologist who teaches at the University of Toronto.

When we sit, our entire metabolism slows down. We are more likely to develop the "metabolic syndrome" — a group of conditions that includes excess abdominal fat, high blood pressure, high blood sugar, and abnormal cholesterol.

If you have at least three of these risk factors, you have higher chance of developing heart disease, diabetes, and certain cancers.

The most worrisome effects, Alter says, actually appear in those of us who sit nine hours or more a day. "The risk of disease increase — cancer, heart disease and stroke."

When he gets sedentary patients, Alter prescribes exercise like a drug. 'I get them to start very small — five minutes a day — and I build them up," he says.

Why is exercise so good for us? Think of it as undoing all the bad things that sitting does. Our metabolism increases, lowering fat and sugar levels in our blood and raising levels of HDL cholesterol — the so-called healthy cholesterol.

Exercise makes your cells crank out more energy, helps your heart pump more blood, and your lungs bring in more air.

"To the extent we think oxygen is the golden nugget to live on earth, our use of oxygen is really important," Alter told Barron's. "The more fit we are, the more our blood carries."

Duke's Kraus came up with his magic number from research that tracked step counts. Eight hours of sitting, 13,000 steps. Every additional hour of sitting requires another 1,000 steps of walking.

And it stands to reason if you sit less, you don't have to put in as many steps. Like Kraus, walk when you talk on the phone. You can pace around the living room when you're watching TV instead of plopping down on the couch.

But what about when you're on the job? There are efforts to get employees up at work. Walking during meetings is an idea that UCLA's Burton Cowgill is a fan of.

"We engineered sitting into our lives, and now we're in the process of engineering not sitting into our lives," says the associate professor of public health. "We were hunters and gathers since early man, now the food is at the corner."

Cowgill recommends taking the stairs instead of the elevator and getting up every 30 minutes and moving around for a few minutes.

"You're breaking up those long bursts of sitting," he says. "Those micro doses of movement throughout the day can counteract the effects."

Now, can we make sitting more healthy? Marc Hamilton, a physiologist at the University of Houston, thinks so.

He developed a sitting exercise called the soleus push-up. You constantly raise and lower your heels, like the seated calf raises that weightlifters do.

Hamilton calls it the soleus push-up because it works the soleus muscle, which runs from just beneath the knee to the heel. It's one of the main muscles we use when we walk. It can fuel itself for hours from sugar and fat in our blood.

And he stressed that we should do the soleus push-up for big chunks of the day — because even though it doesn't offer the full benefits of exercise, it offsets the metabolic damage of sitting for long stretches.

"The soleus is a very unique muscle with a capacity for great endurance, " Hamilton told Barron's. "When it's not competing with other muscles, it gets to grab on to as much glucose and fat as possible."

Write to Neal Templin at [email protected]

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