Experts stress importance of exercise in combating risks of obesity

Many of the experts at a recent obesity symposium highlighted the need for an increase in physical activity, starting young, to help combat the risks of obesity.

Obesity: A Global Perspective from Molecular and Integrative Physiology to Individual Health brought experts from York University and France together to discuss issues that affect obesity. The two-day symposium in early November, sponsored by the Consulate General of France in Toronto, York’s Faculty of Health and York’s Muscle Health Research Centre, looked at obesity from a global perspective using a multidisciplinary approach.

“York’s researchers are working with partners in industry, academia, government and the broader community to advance critical discovery in health research and to enhance health and health care, both in Canada and worldwide,” said Robert Haché, York’s vice-president research and innovation. “The symposium on obesity is an excellent example of how our international partnerships contribute to the advancement of research in these important areas.”

One of the speakers was Dr. Jean-Michel Oppert, a nutrition professor at University Pierre et Marie Curie in Paris, France, and head of the Department of Nutrition at Pitié-Salpêtrière university hospital. Oppert talked about wanting to create a bridge between research and clinical work. He is interested in human movement, sedentary movement and light or moderate movement.

There is a global epidemic of obesity, said Oppert. The increase in obesity has been most dramatic in the United States and Mexico (now at about 35 per cent of the population in both countries compared to 15 per cent in 1992). By comparison, obesity rates in European countries are still low, but they have nearly doubled in more than 15 years with France, for example, seeing an increase to 14 per cent of the population, up from eight per cent in 1997. Canada has also seen a noticeable increase in obesity rates, which have increased from less than 15 per cent in 1992 to nearly 20 per cent today. What leads to obesity? Oppert pointed to food production, consumption, individual activity, as well as environmental drivers that lead to behaviour patterns of obesity.

People who walk briskly at least once a day have a 34 per cent decreased risk of diabetes, he said. In France, 10 per cent of people cycle, while 40 per cent walk every day.

To maintain health, exercise is important. It should comprise at least 75 minutes a week and can be light, moderate or vigorous in intensity to be beneficial physically and metabolically. What is needed, he said, is a multi-level approach that looks at everything from behaviour to the environment. Simply increasing leisure-time activity is not enough.

"Obesity and its attendant problems, including diabetes and heart disease, is a global epidemic that requires a global response," said York's Faculty of Health Dean Harvey Skinner. "Working with international partners such as the University of Avignon, York's Faculty of Health is leading the transformation toward wellness and prevention first, then health-care when needed, to ensure that health and health-care systems worldwide are effective and sustainable."

York Professor Angelo Belcastro, chair of the School of Kinesiology and Health Science at York and Active Health Kids Canada, suggested using guided active play to increase the physical activity of children. A novel approach would be to use self-paced games to establish physical activity trends for children. Most children do not get enough daily exercise.

The solution, he said, was to develop child physical activity guidelines and to raise physical activity levels through school and sports. Currently, most community programs do not provide a high enough level of physical intensity. To increase that level, the children need to enjoy the activity and be motivated to continue it, although having fun is not all that’s required.

Some of York’s Kinesiology and Health Science students are involved in providing a program called Kin Kids at the Driftwood Recreation Centre in the Jane and Finch community. The program involves parent and child feedback to provide activities that the children will participate in. The children in the program also wear monitors for test results to see if the intensity level of the program is making a difference.

York Kinesiology and Health Science Professor Chris Arden talked about the need for obesity prevention in both children and adults, rich and poor. Arden said that physical activity can modify the health risks associated with obesity as can losing a realistic amount of weight, five to 10 per cent of body weight. Too many obese people, women in particular, think they have to lose a large amount of weight to see health benefits, but that’s not the case, said Arden. In fact, weight cycling, losing and then gaining weight over and over, has been linked to higher rates of diabetes. It’s better to take off less and keep it off.

About 17 per cent of the poorest people are obese compared to about 12 per cent of the richest. Only 14 per cent of Ontario children and youth meet the guidelines for how much someone should walk every day. In the Americas, 43 per cent of the population is inactive. Being active plays a major role in preventing obesity, said Arden.

The second part of the symposium discussed how obesity alters the human body’s functions, putting obese individual at risk for Type 2 diabetes and cardiovascular diseases. Statins are the most prescribed drugs to prevent cardiovascular diseases but Statins might, paradoxically, promote diabetes said Robert Tsushima from York’s Faculty of Science, during his talk that reiterated the need for obesity prevention.

Whole body inflammation emerges as one of the major causes that alters health in obese individuals. Dr. Anne Bouloumié from the Institute of Metabolic and Cardiovascular Diseases at Toulouse University discussed how immune cells present in fat tissue might promote inflammation. Professors from York and France also discussed the mechanisms controlling the balance between energy intake and energy expenditure. For example, Dr. Yves Boirie from the Centre Hospitalier Universitaire de Clermont-Ferrand stressed the importance of keeping muscle mass through proper nutrition to maintain energy expenditure for obese individuals.

The symposium also featured round table discussions on such topics as fitness behaviour and obesity, energy metabolism and the molecular basis of obesity. This has been an opportunity to develop new collaborations between York’s Kinesiology and Health Science faculty members and the French visiting scholars. In addition, there was a poster exhibition highlighting the latest research from undergraduate and graduate students, as well as postdoctoral fellows from York’s School of Kinesiology and Health Science and the Department of Biology.

As part of the symposium, York’s Faculty of Health and the Université d’Avignon signed a memorandum of understanding that will see research exchanges between the two universities, as well as a commitment to explore experiential education opportunities for students.

"York's School of Kinesiology and Health Science is proud of our research collaboration with colleagues from a number of distinguished French universities, hospitals and research institutes," said Belcastro. "Together we are charting new ground on important societal health issues as exemplified by the obesity symposium. We are also delighted to enter into a new partnership with the University of Avignon that will see our faculty and students engaged in the sharing of courses, internships, placements and collaborative research activities."