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.

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Sowing seeds of learning

Sharon Oosthoek | April 27, 2015

In the mid-1990s, Maurice DiGiuseppe found himself wandering around a school garden in Hamilton, marvelling at how teachers had incorporated it into a novel lesson plan. The student-run garden at Saint Mary Catholic Secondary School was entirely taken up with plants mentioned in the Bible. Each plant was labelled with its history and use. Strategically-placed benches encouraged students to sit and read. This was thinking outside the plant box, he said to himself, and decided to make a research project out of leveraging school gardens to teach parts of the curriculum — including math and social science — not normally connected with gardens. "Environmental deficit disorder is a big theory in education right now: students are not connecting with nature," says DiGiuseppe, a professor of education at the University of Ontario Institute of Technology. "I think there is truth in it. But gardens can help with more than that." Since that day in Hamilton, DiGiuseppe has accumulated a wealth of knowledge about what works and what doesn't when connecting gardens and learning. His current project ­— case studies of four Ontario schools — is meant to guide teachers to make the most of their school garden. His research subjects include a high school in Peterborough where the teacher in charge of the student-run garden is using it to teach math, economics and social science, in addition to more obvious classes in science and geography. Students not only take care of the vegetable garden, they pickle and can produce for sale and use the proceeds to make micro loans of $200 to $300 in the developing world. The students then follow their borrowers' progress in implementing their business plans and write up posters and multimedia documentaries describing their findings. Each class is a focus group DiGiuseppe and one of his graduate students sit in on planning sessions for each school garden, observe students as they plant and weed, and even accompany them on field trips to buy materials and learn how to manage pests. "We are treating each class as a focus group. At the end of this, we'll have a multi-media case study to present," says DiGiuseppe. But it's not all sunshine and roses. He will also chronicle the challenges involved in making school gardens work. For example, getting school boards to provide a suitable parcel of land usually involves a lot of red tape, he says. And plans to have students build their own raised planting boxes can run into road blocks connected to building and safety standards. With about a year's worth of data under his belt, DiGiuseppe is ready to begin disseminating his findings this summer at international educational conferences. He also has plans to publish his research in educational journals. "This is fabulous stuff," says DiGiuseppe, and the word "really needs to be spread."

Novel energy retrofit

Noreen Fagan | April 20, 2015

From the outside, the Victorian house at 31 Sussex Ave. in Toronto echoes the romanticism of a by-gone era but, once inside, the building transforms into an example of 21st century technologies. The 1879  red brick home is the stately research subject of Kim Pressnail, a professor of civil engineering at the University of Toronto and Russell Richman, a professor of building science at Ryerson University. The University of Toronto-owned house is part of a low-energy retrofit project designed by Pressnail and his former student, Richman. The project explores new and innovative approaches to low-energy housing. In 2013, the Sussex house was retrofitted to incorporate two-nested thermal zones. The box-within-a-box consists of a core and perimeter zone, each with separate temperature controls. The core contains the most commonly-used spaces such as the kitchen, dining room, bathroom and master bedroom while the perimeter contains non-essential spaces such as the ballroom and spare bedrooms. The house uses radiant floor heating, and has triple-glazed windows and foam insulation.  But the key to saving energy lies in the ability to keep the two separately insulated thermal zones at different temperatures, which is what Pressnail and his team did for one year, beginning in December 2013. “We started out by heating the whole building, then gradually turned the heat down in the perimeter,” says Pressnail. In January, the permimeter's thermostat was set at 21 C. This allowed the researchers to see how the house would perform if all areas were heated.  In February and March, the perimeter air temperature was gradually reduced to 5oC. This provided the researchers with the opportunity to evaluate the response of the ornate plaster ceiling in the ballroom.  Generally, the perimeter areas can be turned down to 5oC or the average outdoor monthly temperature whichever is greater in order to achieve maximum energy savings during the winter season. But in April, as outdoor temperatures began to climb, the team allowed the perimeter temperature to increase to 10oC. “The goal was to save energy and increase the durability of the building – not degrade it,” says Pressnail. Tenants to move in The overall target was to save 75 per cent more energy compared to a home built to the 2012 Ontario Building Code (OBC) standards. In fact, the savings were 65 per cent, but if the perimeter had been operated in the maximum energy savings mode for the entire winter, they would have been closer to their goal, says Pressnail Although the initial research period has ended, the team will continue to record energy usage after new tenant – a visiting professor –  moves in April 1. “We are going to monitor how the occupant, who has been given the tools to save energy, will run the house. We are going to sit back and see what happens,” says Pressnail. While Pressnail keeps tabs on the Sussex house, his future projects will include either building thermal zones into a new home or retrofitting a modern building. Although research done at Sussex house shows that thermal zoning is environmentally friendly, Pressnail doubts people will be rushing to retrofit their houses anytime soon. At a time when natural gas and oil prices are low, the cost of retrofitting outweighs the energy savings. “The game-changer will be when people start paying the true cost of what the energy is doing to the environment,” he says.  

Bathroom talk

Sharon Oosthoek | April 16, 2015

Alex Mihailidis is known as "the talking bathroom guy" for his research into computerized devices designed to help those with dementia live more independently in their homes. The University of Toronto biomedical engineer created a bathroom with sensors to detect when someone standing idly at the sink has forgotten how to wash their hands. The sensors trigger a gentle voice that leads them through the process of turning on the tap and using the soap. And if they need extra help, there is a video screen in front of the sink to demonstrate proper technique. Mihailidis's bathroom adapts to the user so that if it's their habit to take 30 seconds to lather up, it will wait 30 seconds before prompting them to rinse. He has put his bathroom through a series of rigorous tests at the Toronto Rehabilitation Institute's mock apartment, set up for studying assistive technologies in the home. People with mild to moderate Alzheimer’s disease living in long-term care homes in Toronto came in to help, showing that they are able to complete 25 per cent more of the required steps with the bathroom's prompts. Testing is crucial, says Mihailidis. Anywhere from 70 to 90 per cent of assistive devices are abandoned after a short period of use. Often it's because designers haven't deeply considered users' abilities, education and cultural or social backgrounds. Mihailidis is just wrapping up a research project to understand how these factors affect people's use of assistive technologies. The project relies on questionnaires, focus groups and interviews with caregivers. "Technology is the easy part" His resolve to get it right comes from a chance meeting years ago, with an engineer whose wife had Alzheimer’s disease. The man talked about how both he and his wife were embarrassed when he had to help her in the bathroom. He said he wished there was some device that could prompt his wife to use the toilet and sink, and give her back her dignity. "That kind of stuck with me," says Mihailidis. "Technology is the easy part. I mean it may take us a few years to perfect it. But what we really need to understand is how this technology affects people's lives." Mihailidis is also working on an interactive robot that can help people with dementia complete daily tasks such as making a cup of tea. Unlike the bathroom technology, which stays put, the robot can follow someone into the kitchen. Preliminary tests at Toronto Rehab show people with dementia are willing to interact with the robot and follow its prompts. Mihailidis's team — keenly aware that our population is aging ­— is encouraged by these results. "We are still in the research phase. These are complex technologies," says Mihailidis. "But our goal is have people use these technologies in their home to keep them living there independently as long a possible."

Healing gardens

Araina Bond | April 13, 2015

Nathan Perkins is dedicated to improving people’s health, one woodland path at a time. “Connecting with nature is incredibly important for health and wellbeing,” says the associate professor at the University of Guelph’s School of Environmental Design and Rural Development. His work is part of a body of research that demonstrates the powerful benefits that come from interacting with natural environments. In fact, studies show even a five-minute walk outdoors can lower blood levels of the stress hormone cortisol. Whether it’s as complex as a walk through a labyrinth or as simple as being able to move a chair to a place in the sun, research shows that a vital part of happiness and healing involves being in a healthy environment. While there are many studies that link nature – even something as simple as gardening or caring for a house plant – with good physical and mental health, Perkins has seen the effects first hand. He recalls keenly how a staff member at a health centre he helped design once told him: “What a huge difference this design makes for our clients. They are self-medicating on nature!” Perkins also works with schools and other institutions, and he’s designed projects on three continents. While each is different, they are all about finding the best ways to connect people with nature. His first major project was working with Guelph's Homewood Health Centre, a psychiatric hospital with programs for helping patients deal with addictions. “I was their designer in residence,” he says. “It was the highlight of my academic career.” Participatory design crucial to project Since the historic Homewood Health Centre houses a daycare where Perkins’ own children attended, the beautiful grounds are also an opportunity for stimulating interaction. “The clients got so much joy from watching the kids play in the gardens,” he says. “But the children also learned that people with addictions and mental health issues are just regular people.” Perkins explains that environments that inspire wellbeing are about more than just beautiful flowers. He believes in a process of participatory design from beginning to end. Patients and staff at Homewood, for example, were not only consulted throughout, but were also involved in long-term initiatives such as the herb garden and nature trail. “We all need a pilgrimage experience, a contemplative meditative space. It can be as simple as having chairs that people can move to create their own space,” he says, pointing out that in many institutions such as hospitals, chairs are bolted to the floor. Perkins has published several studies showing the benefits of involving staff, patients and even visitors in the design process. In designing institutions, he says, so much of the process is focused on long term cost-saving measures. “That’s how you end up with windows that don’t open,” he explains. “I’m a big believer in windows that patients can open. If you can’t have that, it could be something as inexpensive as putting a bird feeder outside the window.” Perkins notes that research shows small changes, such as having a hospital room with a view, can lead to shorter stays and less pain medication. In fact, he still treasures a letter sent by one former patient with addictions issues thanking him for the woodland trail he’d designed. She said it gave her hope and helped her heal. “I want to change the world,” says Perkins, and there is little doubt that he is on the right path.

Fix that leaky pipe

Sharon Oosthoek | April 9, 2015

There was a time when mould in your house — even so-called toxic black mould — was considered a mere aesthetic problem. "Until 1988, it was assumed if mould grew in a building, it was just ugly and not much of a health hazard," says David Miller, an expert in fungal toxins and allergens at Carleton University. "That assumption was absolutely wrong." Miller's research has been instrumental in changing our understanding of how mouldy homes harm our health, and in creating building codes and government policy to lessen those effects. Mould is a colloquial term for fungi that grow on things such as food and damp building materials. When it reaches a critical mass on the wall or a cold corner of a house, bits of the fuzzy stuff break off and become airborne or collect in dust. These fragments contain toxins and proteins, some of which are allergens, and all of which are small enough to travel deep into the lungs. People living or working in damp and mouldy buildings are at increased risk for asthma and respiratory problems such as colds and flu. Miller helped establish this link by honing techniques for assessing exposure in a way that is relevant to our health. In partnership with a large clinical lab, he works with blood samples from people already known to be allergic. This means their blood contains antibodies produced in response to various allergens, including those from mould in their homes and workplaces. Miller then uses these antibodies to "mine" for allergenic proteins produced by mould. He does this by extracting proteins from the most common species of fungi that grow on damp building materials. These are then purified on a special gel that also separates them. Next he spreads a dilution of the antibodies over the gel. "If there is a protein that the antibody recognizes, it will stop there and stick," he says. This tells him that the proteins from building samples come from moulds that have an adverse affect on our health. Don't forget to ventilate Such research is especially important in Canada, where children — whose developing immune systems make them vulnerable — spend about 90 per cent of their time indoors. That's a problem, given that between 10 and 30 per cent of homes in North America have moisture issues leading to mould growth. Part of the reason for this, says Miller, is we began to better insulate our homes in response to the 1970s' energy crisis. That's a good thing for reducing energy and greenhouse gas emissions. But for a long time we didn't pay enough attention to proper ventilation, giving mould a damp breeding ground. "A typical family of four emits two to seven kilograms of water every hour from things like cooking, cleaning, showers and faulty venting on clothes dryers," says Miller. "If it isn't vented properly, the water goes into the fabric of the building." Thanks to the work of Miller and others, we now better understand the risks. This has led not only to building codes requiring better ventilation, but also to public education campaigns encouraging people to repair leaky pipes, use kitchen and bathroom exhaust fans and make sure clothes dryers are properly vented. "Changing building codes requires evidence. Making public policy requires evidence," says Miller. "That's where I've tried to make my contribution."
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