IE 11 is not supported. For an optimal experience visit our site on another browser.

Sitting all day? How much is too much and why exercise can help

New studies pinpoint the exact number of hours of sitting that hurts our hearts.
/ Source: TODAY

Too much sitting is bad for your health, but there are simple ways to counteract the damage.

At least one hour of daily exercise appears to get rid of the increased risk of dying that comes with sitting for more than eight hours a day, according to a review of studies published in The Lancet on Wednesday.

Moderate exercise is key

For both men and women, the key is 60 to 75 minutes of moderate-intensity exercise a day — and there's no need for a gym. Everyday activities such as brisk walking and cycling, work just fine, said Ulf Ekelund, a professor at the Norwegian School of Sport Sciences and the lead author of the paper.

“If physical activity were a drug, if would be prescribed against almost every non-communicable disease, including hypertension, diabetes, cardiovascular disease, cancer,” Ekelund told TODAY.

Related: Sitting at a desk all day? Here's what you should be doing instead to stay fit

Sedentary at work and at home?

Some forms of sitting are worse than others. Lounging in front of your TV, for example, is more harmful to your health than sitting in a cubicle, possibly because you get up less frequently and snack more when you’re binge-watching your favorite show on Netflix.

Exercise reduces —but does not eliminate — the higher risk of death that comes with watching TV for five or more hours.

The findings are a wake-up call for those who are both sedentary at work and at home.

“Long sitting hours should be avoided and the combination of occupational siting and leisure sitting in the evening is possibly very detrimental,” Ekelund said. However, researchers also found the prescribed amount of physical activity had the same good effects on people who sat for up to 10 hours a day or more.

The results are based on an analysis of 16 studies involving more than one million people.

Related: This exercise is the superfood of fitness, experts say

Sitting's tipping point

So how much sitting is too much? The tipping point, at least in terms of heart health, is 10 or more hours a day, according to a new report published in JAMA Cardiology. And that's taking into account heart disease risk factors, like high blood pressure and glucose levels, — which, it turns out, are exacerbated by excess sitting.

So, really, it’s even worse than it sounds. That’s because the researchers wanted to figure out how much damage excess sitting does if all the other risk factors are corrected. In other words, they wanted to know if excess sitting would still be harmful to someone who's brought down his or her weight, blood pressure, and cholesterol and also exercised more.

At 10 hours the risk of heart attacks and stroke increases by 7 percent. And the risk goes up with every sedentary hour beyond that, rising to 13 percent with 12 hours of sitting and 22 percent with 14 hours.

Related: Sitting may raise the risk of cancer

The report's researchers combined the data on 720,425 people from nine prospective studies in what is known as a meta-analysis, which gave them the ability to see smaller effects.

No one, including the report’s authors, knows why sitting is so harmful. “There may be an unknown factor mediating it,” says the report’s lead author, Dr. Ambarish Pandey, a researcher in the division of cardiology at the University of Texas Southwestern Medical Center. “That’s something that needs to be studied further.”

They do have theories, however. “It’s thought that when we are sitting and our skeletal muscles are inactive it leads to adverse biochemical reactions, such as inflammation and insulin resistance,” says Dr. Erin Michos, associate director of preventive cardiology at Johns Hopkins School of Medicine. Michos recently spoke about the topic at the Robb Report’s second annual Health & Wellness Summit.

Simple tweaks, big results

For those forced to spend many hours sitting during commutes and in workplaces, the situation may seem hopeless.

But a few simple tweaks to your routine can work wonders, says Michos, associate director of preventive cardiology at the Johns Hopkins School of Medicine.

“For every 20 minutes of sitting, you can try to add in 8 minutes of standing and 2 minutes of moving,” she adds. “I set my alarm so that I regularly take a loop around the hallway. I try to do walking meetings. Anything you can do to build in movement. And obviously the more moving you’re doing the better.”

Related: Staying active all day linked to longer, healthier life

Michos also suggests walking down the hall to talk to a colleague in person, parking your car in the back of the lot, and taking stairs instead of the elevator.

Evidence shows small changes like these have measurable effects, Michos says, pointing to a study published in the European Heart Journal, which showed that “replacing sitting time with standing or stepping is associated with improvements in surrogate markers of risk like body mass index, lipids and glucose.”

So, it’s entirely possible you could improve your health by simply strolling to the water cooler a few times each day.