Beware the chair

Study after study has highlighted the dangers of a sedentary lifestyle that includes extended periods of sitting, and the catchphrase “sitting is the new smoking” has gained traction in the media and in popular consciousness. We asked U of T’s Greg Wells how bad sitting really is. Wells is an assistant professor in the Faculty of Kinesiology and Physical Education at U of T and an associate scientist in physiology and experimental medicine at the Hospital for Sick Children. His research is focused on developing new ways of treating disease using exercise and nutrition.

Jenny Hall: We’ve been hearing a lot in the media lately about the health threats of sitting too much. Is sitting actually that bad? Is it really “the new smoking” as we keep hearing?

Greg Wells: The physical inactivity epidemic is causing all sorts of health problems. It is associated with almost every chronic disease on the planet, including cancer, cardiovascular disease and type 2 diabetes. The World Health Organization has stated that physical inactivity is one of the leading health concerns for the planet, and that it is closely associated with increased rates of non-communicable diseases. Non-communicable diseases are the leading cause of death on every continent except Africa. If it’s not the world’s number one health concern, it’s pretty close.

JH: Is there any research on how much sitting is too much?

GW: We know a couple things for sure. First, humans need to be vigorously active for at least an hour a day. A very small percentage of our society achieves that. Vigorous activity is something above and beyond just walking. Your heart rate is needs to be elevated, and you need to be engaged in something that’s physically demanding for you. An hour of fast walking is an example of vigorous activity.

The other thing we know is that the more physical activity we can incorporate throughout the day, the better. This is because sitting is an independent risk factor. The more you sit, the worse your health is going to be. So in addition to getting the one hour of vigorous physical activity, the more you can intersperse physical activities like walking or moving or getting up to move around throughout the day, the healthier you are going to be.

JH: When you say sitting is an independent risk factor, does that mean that even if you get the hour of vigorous activity a day, you’re still at risk?

GW: Yes. Consider an office worker who’s going to the gym religiously for an hour a day. That’s great. They’ll be way better off than if they never did it at all. The message isn’t don’t do that one hour of exercise—it’s incredibly beneficial. We know that vigorous exercise decreases your risk of breast and colon cancer by up to 50 per cent. But sitting all day is still a problem in and of itself that needs to be addressed.

JH: Are there any guidelines for the other kind of activity you talked about—the kind we should try to be interspersing throughout the day?

GW: The best idea is to try to add short bouts of activity throughout the day. I use the 20/20 rule. For every 20 minutes of sitting, stand up and stretch for 20 seconds. Beyond that, within every two-hour block, try to find 15 minutes to do some activity, be it walking or stairs. Even just standing for a while is better than sitting down.

I tell people to stand up in meetings. If everyone else is sitting, find a spot to stand up in the back. If you’re doing a phone call, get up and do it with headphones while you’re standing.

Fifteen minutes of activity every two hours is a tall order if you’re in an office environment.

It is—until you begin to consider the significant damage that sitting causes. The other thing we have learned that’s emerging is the powerful benefit of physical activity for cognitive performance. We now know that physical activity and exercise activate the areas of the brain associated with memory, learning, problem solving and concentration. So an office worker might think they don’t have time to stretch and move, but I would say to them, you can’t afford not to. Not only is your health going to improve, but your performance is going to dramatically improve as well.

JH: So there’s case to be made the physical activity is good for your brain, too?

GW: Absolutely. I watched a documentary on Bob Marley recently. He has a reputation of being this pot smoking guy, but he was a relentless perfectionist. He didn’t let the Wailers play live until they’d practiced for two years. Before they went into recording sessions, he would make everyone play soccer on the beach. They would never go in to play unless they had been exercising beforehand. Or, if you read Steve Jobs’s biography, he never did meetings sitting down. His big creative meetings were always done walking.

I think there’s a real sound physiology to these stories, and good rationale for incorporating physical activity into your day. You’re changing the way your brain works. You’re actually flooding the area of the brain that you’re using with oxygen and nutrients. It’s like flipping a switch. The fact that we try to do creative mental work sitting down goes against the way the body and brain are meant to work.

JH: What actually happens in your body when you sit for extended periods of time?

The main thing is decreased blood flow. When you move, you push fluid through all of the tissues in the body. That is one of the main ways the body fights off illness, by pushing fluids through what is called the lymphatic system. You actually have two full circulatory systems in your body—most people don’t know that. You have your blood system that everyone’s aware of, but you also have the lymphatic system. Fluids moving through the lymphatic system are how the body catches viruses and bacteria and other invaders and filters them out and kills them. So the primary way to stay healthy is to get up and move. Beyond decreased circulation, you also get decreased flexibility and decreased nutrients supplied to muscles and the brain.

JH: It sounds like stagnation.

GW: It’s absolutely stagnation. Think about a fresh flowing stream versus water that sits. Sitting water becomes stagnant with low oxygen, and viruses and bacteria grow in it. There’s a similar effect inside the human body.

There do seem to be some parallels to smoking here if you think about sitting as a public health problem. A huge public health push—and some high profile lawsuits—in the latter part of the twentieth century changed cultural ideas about smoking. Does something similar need to happen with sitting?

We need intervention and education at every single level. We need to get physical education back in schools and to make sure that communities are built with sidewalks and parks. We need to make sure that cities get built so that people can ride their bikes. We now know enough that people should know better. I think it’s possible that employers could be held accountable in the future for not providing the opportunity for employees to be as healthy as they could be, given what we now know. We need a tremendous push on education about the benefits of physical activity and the risks of inactivity.

Tagged: Health, Stories

Share: Print

Leave Comments

Blog Posts

A matter of will ...

Cherri Greeno | January 14, 2015

New research from the University of Waterloo explains why our brains often fail to turn intention into action, and why this gap can be overcome. read more »

Adjusting goals is not ...

Deborah Durbin | January 12, 2015

On January 1st many people set bold exercise goals for themselves as part of their New Year resolutions. Come Valentine’s Day, though, most of those goals have fallen by the wayside, tossed aside along with empty heart-shaped candy boxes. read more »

How to set realistic ...

Araina Bond (with files from Patchen Barss) | January 9, 2015

Making New Year’s Resolutions and sticking to them are two very different things. Two Ontario researchers have each discovered different ways to make reaching goals more likely. read more »

Let shopping be your ...

Noreen Fagan | December 18, 2014

Here’s a fun fact – Canadians eat more sushi than the Japanese. At least that’s what Mark Cleveland says, and he should know. Cleveland is a professor of marketing at Western University. His research focuses on the integration of cultures on a global scale and the effects of cosmopolitanism, which according to Cleveland is, “the cultural openness and the ability to successfully navigate between different cultural groups.” In other words, people who want to understand and experience other cultures do so by fully immersing themselves in that culture. “You want to live the life of cultural authenticity, by trying to understand the culture through that culture’s eyes,” he says. Cleveland’s interest in cultural openness started when he was a Master’s and then a Ph.D. student at Concordia University in Montreal. He started researching how new immigrants, primarily ethic minorities, adapted to Canadian culture by finding ways to combine their traditional identities, culture and values into mainstream society. “I have always believed that just because you learn another culture does not mean you give up the original culture. You can be bicultural or multicultural and the two can reinforce each other,” says Cleveland. “Not only are minorities affected by cultural exchange but the majority are as well.” Canada’s multiculturalism prompted Cleveland to extend his research into globalization, with a focus on how global cultures affect majority populations around the world. In the last decade Cleveland has conducted research in 15 to 20 countries exploring cultural exchange and cosmopolitanism. He says a person no longer has to travel abroad – although it helps – to become cosmopolitan. A person can experience different cultures in the comfort of their own home or neighbourhood, simply by watching TV, surfing the Internet, playing videos on You Tube or buying and consuming different products. “When we buy products, and types of brands and the reasons for buying them, they are like extensions of ourselves,” he says. So how do the sushi–eating Canadians fit into all of this? Cleveland believes if a person wants to experience cultural authenticity they will gear their shopping towards achieving that aim. In other words, a person is not going to go for the North American version of sushi (think Californian Roll), when they can get the real thing – think Unagi. He says there is probably a general global trend towards cultural openness as people become more educated and have more exposure to other cultures but he warns, there is another side. “A lot of people are really opposed to what is happening with Globalization and they see their culture as under threat,” says Cleveland adding that the threat is heightened when people feel insecure. If people are feeling secure in their surroundings (financially, emotionally and physically), the more open they are to cultural exchange and the more cosmopolitan they become. Being cosmopolitan however, does not mean buying local is a thing of the past; in fact what makes cosmopolitans stand out is that they strive for cultural authenticity. “The more cosmopolitan you are means you are not only interested in preserving differences but also interested in the environment, like getting the best locally,” says Cleveland. In terms of cosmopolitanism Cleveland thinks Canadians are more accepting of other cultures. “We are a new country, most of us go back two or three generations and have one or two grandparents born somewhere else. We have a more fluid identity,” he says, adding that as large cities go, Toronto is well integrated. “We are not just living in these areas dominated by our own ethic group, there are more opportunities to mix, and I think that allows us to become more open-minded.”
More Blogs »