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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Timothy Muttoo (University of Waterloo) with clay filter

Low tech water filter

Christine Bezruki | July 27, 2015

It may use the most simple of technology, but a new water filtration system is transforming thousands of lives in the Dominican Republic. Designed by University of Waterloo Masters of Public Health student, Timothy Muttoo, in partnership with the non-profit organization FilterPure, the new filters use locally-sourced clay, sawdust and particles of silver to remove 99.99 per cent of all water contaminants. “It really is an engineering innovation,” says Muttoo, who redesigned the composition of FilterPure’s original product to lower production costs and make the filters more affordable in the Dominican. “So many well-intentioned projects fail in developing countries because they aren’t sustainable or affordable.” Water is first step out of poverty One of the Caribbean’s poorest countries, 1.6 million people in the Dominican Republic do not have access to safe, clean water. UNICEF estimates that 50 per cent of children live in poverty, with 30 out of every 1000 dying before the age of five as a result of impure water and unhygienic living conditions. “Without a safe, accessible water source, communities get trapped in a vicious cycle: poverty contributes to access problems; access problems perpetuate poverty,” says Muttoo, who launched his own non-profit, H2O 4 ALL, in 2008. “The effects of unsafe water and poor sanitation are devastating, but it is a completely solvable problem.” The innovative bowl-shaped filters work by distilling dirty water through a porous clay membrane and into a clean receptacle bucket.  The water is brought to safe drinking quality standards and is easily accessed from a spigot. Working with, not for, communities This year Muttoo and FilterPure plan to distribute 4,000 filters to families across the Dominican. Each filter can produce up to 30 litres of clean water per day. As part of the initiative, Muttoo will study the social uptake of the technology as well as work alongside community health leaders for training and monitoring of the filter usage and evaluating health impacts within impoverished communities. “A key to sustainability is working with the communities, not for the communities,” said Muttoo. Since its inception, H2O 4 ALL has led projects in 10 different countries around the world— all with the mandate of working with local partners on the ground. Last summer Muttoo partnered with Save the Mothers and United Nations University in Uganda to drill a borehole well for Kawolo hospital, which serves Lugazi’s 1.2 million inhabitants. The well is an expansion of a rainwater filtration system he installed in 2012 for the hospital’s maternity ward — the hospital’s first ever access to safe water. As a result of both projects, infection rates at the hospital have plummeted to almost nothing. “Thousands of people are alive and healthy because of collaborative projects like these and the people that reached out to help,” said Muttoo. “Sustainability, empowerment and health. That’s the power of giving people clean water.”   A  version of this story was originally published by the University of Waterloo.  It has been edited for clarity, accuracy and brevity, and is republished here with permission. 

Braking for water

Sharon Oosthoek | July 22, 2015

A strenuous workout should be accompanied by frequent water breaks, right? Not so fast, says Brock University physiologist Stephen Cheung. While that certainly is the received wisdom, Cheung points out that top-performing athletes almost always speed past water stops in an effort to shave seconds off their time. "Elite marathon runners barely touch water, even on a hot day," he says. "And they lose more body weight through sweat (than others) and have higher core temperatures at the end of a race." In the mid-1990s, the American College of Sports Medicine recommended at least the full replacement of sweat loss during exercise. In 2007, it revised its guidelines to 400 to 800 millilitres of water per hour, and recommended dehydration be kept to less than 2 per cent of body weight for health and performance. Yet when Cheung looked more closely at the studies backing these guidelines, he found a crucial flaw: they didn't distinguish between being dehydrated and being thirsty. Instead, studies denied participants water while exercising in the heat, making them hyper-aware of their lack of hydration. "Doing that changes not only your physical hydration status, but your psychology," says Cheung, a competitive cyclist. "You are setting up a mental template for how hard you're going to cycle or run." Wiping the template clean So Cheung set up his own study, putting 11 competitive cyclists and triathletes through a 90-minute bike ride at half their aerobic capacity, followed by a 20 kilometre time trial. All participants had an IV in their arms, but only some received saline to replace lost sweat. The saline was warmed to body temperature so they couldn't tell. All participants also sweated out at least 2 per cent of their body weight before the time trial. Crucially, neither the participants nor the researchers knew if they were being hydrated. A paramedic tasked with monitoring their vital signs was the only one who knew, and he remained carefully hidden behind a curtain so as not to influence the outcome. The results? There was no difference in performance between those receiving saline rehydration and those receiving nothing. And there was no difference when Cheung further divided the group into those who were hydrated and not thirsty, hydrated but thirsty, dehydrated and thirsty and dehydrated but not thirsty. The takeaway message, says Cheung, is that losing 2 to 3 per cent body weight due to dehydration after two hours of exercise does not impair performance. “So drink according to your thirst, but don’t obsess about drinking or worry that you can’t perform at your best without fluids,” he says.
River rapids

Tribal waters

Noreen Fagan | July 20, 2015

Dan Walters is interested in water — especially in its emotional, spiritual and social connections to First Nation communities. A professor of geography at Nipissing University, Walter's current project assesses risk levels in drinking water and wastewater in the Dokis First Nation, located on the French River near Georgian Bay. Walters' anthropological approach examines the community's physical and cultural relationship to its tribal waters. It is, he admits, an approach at odds with Ottawa's focus on the technological aspect of First Nations' water systems. “It goes beyond understanding about water that comes out of taps, " he says. "The water quality in the ground affects medicinal plants and animals the Dokis Nation consume.” Walters's research is about making clear the gaps in assessments carried out by Aboriginal Affairs and Northern Development Canada (AANDC), and offering suggestions for filling them. Muddied waters For example, AANDC research is based on scores which distort what communities value and muddy the impact policies and funding have on water systems, he says. A high score means a community has potential health and safety concerns while a low score implies the opposite.  The scores are important because communities with high-risk levels are given priority funding. But in the 2003, 2006 and 2010 federal assessments across Canada, First Nations' risk scores changed with each new assessment. In 2003 there were 218 high-risk systems, in 2006 that number fell to 178, while in 2010 there were 314 high-risk systems, out of a total of 807 communities. Lost in these numbers was any understanding of whether individual community scores had changed over time, to say nothing of why some water systems improved while others were high-risk. “We have no idea how many of those high-risk systems in 2006 are still high risk in 2010,” says Walters. “It is not clear whether the policies and funding have a direct influence on a community’s risk score.” In Walters’ opinion, the government’s technical assessment is limited and contradictory. For instance, in some communities, drinking water was declared safe but the community still received a high-risk score. “This creates a sense of fear in the community,” says Walters, adding that federal assessments also fail to recognize the multiple connections First Nations have with water. In Dokis First Nation, he highlights the importance of spiritual and emotional perceptions of water. Along with Carly Dokis and Benjamin Kelly, anthropology and sociology professors from Nipissing University, Walters has been exploring the cultural and social connections that the Dokis’s have with their water. Walters and his co-investigators are trying to create a new methodology for understanding these connections. It involves assessing how youth learn about the land, how community members are empowered, and how elders are encouraged to share stories about the past, all through community members’ connection with their territorial waters. “I think that our method needs to be used in addition to the federal technical surveys,” he says. " It is about respecting and understanding the value of water beyond just the technological  understanding of water.”
Bay of Fundy

Changing tides

Sharon Oosthoek | July 13, 2015

Tidal speeds in Nova Scotia's Bay of Fundy can reach a staggering five metres per second.  By comparison a very fast river flows at about two to three metres per second, "and you wouldn't want to fall into a current like that," says Queen's University professor in coastal engineering Ryan Mulligan. So it stands to reason that anything slowing that flow would have significant impact on the ecosystem. That includes tidal turbines affixed to the ocean floor, a form of renewable electricity under consideration by Nova Scotia's department of energy. Mulligan's research is providing important insights into how such a field of turbines might affect the bay's powerful currents and its resulting impact on the environment. Tidal turbines work much like wind turbines, the key difference being that tidal currents, not wind, drive the blades that generate electricity. Also, tides are reliable and predictable, unlike wind or solar power, making this form of renewal energy hugely appealing, says Mulligan. Nova Scotia has been operating North America's only tidal power generating station near the town of Annapolis Royal since 1984. But critics say its design is not as environmentally-friendly as it could be. The system relies on tides to fill a human-made reservoir from which water is released as needed to generate electricity. The reservoir has caused river bank erosion and the dam has created a lethal trap for some marine wildlife. Turbines affixed to the ocean floor are a more appealing option. They don't involve flooding a basin and can be designed to allow marine life to swim past. Even so, they are not without environmental consequences. Forecasting tidal flows The difficulty is that there are only a few such installations in the world — most of which are in the United Kingdom — and research into their impact is still in its early stages. This makes Mulligan's work all the more timely. He has developed a sophisticated computer model using existing data on tidal speeds and suspended sediments in the Bay of Fundy. This gives him a baseline against which to measure the impact of a field of turbines on the bottom of the bay. His computer model estimates the turbines' impact by simulating a semi-permeable barrier across Minas Passage, an area of the bay where currents are particularly strong. At their maximum, the currents in the passage could generate about seven GW of power, enough to power roughly 2.5 million homes. That would require a full-scale array of several hundred turbines, which Mulligan's model estimates would result in a drop of nearly 30 per cent in the speed of tidal flows. "This is not a negligible change," he says. The problem with settling sediments Mulligan has calculated that the reduced flow is likely to lead to a decrease of about 70 per cent in suspended sediments in the water rushing through the passage. Those sediments will instead settle out, leading to silting in adjacent channels, shipping harbours and ecologically-productive tidal flats. This is crucial information for other researchers — marine ecologists, harbour engineers and fisheries scientists — who can now build on Mulligan's findings to fine tune predictions about local environmental impacts. "Taking energy out of the system impacts the physical environment," says Mulligan. "It will change the habitat and the species that can live in these places. It could also affect the socioeconomic environment — fishing, aquaculture, navigation. We need to know these things."
Curiosity Crew at Event

Stories from the road

Sarah Binns | July 9, 2015

Sarah Binns is part of our Research Matters team touring the province this summer to spread  the word about research breakthroughs at Ontario's 21 publicly funded  universities.  This summer Alex, Katie, Badri, and I have been travelling from Thunder Bay to Ottawa, and Windsor to Sudbury to promote the amazing research happening at universities across the province.  We’re highlighting 50 game-changing innovations from the last 100 years through fun research-themed trivia. There are some truly impressive game-changers on our list, but the innovations that people feel most connected to are often the ones we least expected. The most memorable moments happen when someone shares with us a personal connection to the research we’re promoting. In Sudbury, we were amazed by the city’s pride about the inclusion of the SNOLAB in our list.  It seems everyone either knows someone who worked there, worked there themselves, helped construct, or visited the underground lab. We’ve also met potato breeder Gary Johnston’s neighbour, and UOttawa law students who took classes with Michael Geist. And countless professors and researchers have dropped by to talk with us about future game-changing discoveries they are working on. For me, the most impressive feature of our list of game-changing research is that its showcases the full breadth of research from a wide variety of disciplines. As classics graduate I am incredibly pleased with the inclusion of historians and theorists, as they most accurately reflect my own research experience. Historian Margaret MacMillan has helped us understand the influence of past events on present policy and international relations, while literary critic Northrop Frye revolutionized the field when he outlined a highly structured, systematic theory of criticism that exists independent of literature itself. Communications theorist Marshall McLuhan made his mark by examining how media changes our behaviours and perceptions according to the way information is structured.  I have enjoy sharing their stories and the unexpected ways in which their work has impacted Ontario, Canada, and the world. Which of our game-changers do you most connect with? Stop by and share your research stories with us at one of the following upcoming festivals: Sunfest in London- July 9th-12th Kingston Farmers’ Market- July 18th Ennismore Shamrock Festival- July 19th Muskoka Ribfest in Gravenhurst - July 24th-26th Kempenfest in Barrie- July 31st- August 3rd We hope to see you there and in the meantime #staycurious!
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