Info and announcements on the prestigious annual prize hosted by McGill University, plus updates on cutting-edge health, nutrition and lifestyle news.
Tuesday, 29 January 2013
Making cities more fitness-friendly
It may not seem obvious at first, but our environment has a major impact on our activity level – and on our health. As the work of Bloomberg Manulife Prize winner James Sallis has proven, the neighourhoods we call home have a lot to do with how fit we are. Last weekend, Sallis, a behavioural psychologist, discussed his research on CBC Radio. http://www.cbc.ca/allinaweekend/health/2013/01/27/making-cities-more-fitness-friendly
Location, location, location Where we live has an impact on our level of physical activity.
James Sallis, a distinguished professor in Family and Preventive
Medicine at the University of California, San Diego, is a leading expert
in the field of policy and environmental influences on physical
activity, nutrition and obesity. His groundbreaking work and commitment
to promoting active health through practical interventions and advocacy
earned him the 2012 Bloomberg Manulife Prize for the Promotion of Active
Health. In advance of his visit to McGill to receive his award, we
spoke with Prof. Sallis about his research and its impact.
(McGill) How did your background as a trained psychologist lead you to your current research?
During the early years of my research, I was interested in
understanding the role peoples’ motivations and other psychological
factors play in an individual’s ability to adopt and maintain a physical
activity regimen. These studies led me to conclude that a complex set
of psychological and environmental factors are at play and that
if we are to be successful in changing behaviour over the long term, we
must modify how we plan and build our neighbourhoods. In recent years, I
have focused my energies on studying how the design of our communities,
transportation systems and parks can help people re-integrate fitness
into their daily lives and have worked to gain buy-in for change from
government agencies and industries. My goal is not to use my research to
point the finger, but to point the direction to solutions.
(M) Why has our environment only recently been recognized as a contributing factor to physical inactivity?
As members of the human species, we are living the dream of our
ancestors: to eliminate back-breaking work. The inventions we have made
and the industries we have created have all been aimed at making our
lives easier. Consider all the labour saving devices we have in our
homes and the high-tech toys that provide us with entertainment. And the
neighbourhoods we have built have been designed around the automobile,
rather than around walking and other forms of physical activity. We have
now reached a point where what we have created is literally killing us!
Chronic disease related to physical activity is now a global pandemic
that is responsible for about 5 million deaths every year. Since we are
not going to reverse this trend by eliminating computers and washing
machines, or by making other changes at our homes and workplaces, we
must re-think our transportation and recreation infrastructures and make
them more conducive to physical ativity.
(M) Are there communities that are successfully working to move in this direction?
Yes there are. Northern European countries such as Sweden, Denmark and
Finland have been pioneers in developing alternatives to an
automobile-centric urban infrastructure. In fact, there are now so many
bicyclists that some cities are having problems with bike path
congestion. Here in North America, New York City has made impressive
headway. Its mayor convenes an annual summit, where various departments
(Health, Parks etc.) outline initiatives that have included the creation
of more parks and the introduction of protected bike paths. Even in
car-dominated Los Angeles, neighbouring Long Beach has been named the
most bicycle-friendly city in America.
(M) What can the average person do to help make their community more conducive to physical activity?
There are many things you can do. If your neighbourhood doesn’t have
sidewalks or lacks park facilities, I encourage you to lobby your local
government. And if you are a parent, you can find out what types of
physical activities your children are involved in at school. If the
school hasn’t already done so, suggest that it implement the SPARK
(Sports, Play, and Active Recreation for Kids) program, which conducts a
popular series of workshops for teachers and physical activity experts.
There is no one solution to the problem of inactivity, but when many
people make themselves heard, change does come.
(M) What does it mean to have been named the winner of the Bloomberg Manulife Prize?
(JS) For someone involved in research related to physical activity, I consider this award to be the equivalent of the Nobel Prize.
Each year the Bloomberg Manulife Prize for the Promotion of Active Health is awarded to a researcher whose work has the potential to improve levels of active health across Canada, and educate the public on fitness, exercise, and healthy lifestyle behaviours.
This year's $50,000 award goes to psychologist James Sallis, Distinguished Professor of Family & Preventive Medicine at the University of California, San Diego; his studies have shown how urban environments shape levels of physical activity, contributing to more thoughtful city planning.
Widely regarded as a leading expert on human behavior and its influence on fitness, Dr. Sallis began his career investigating how to successfully encourage individuals to incorporate physical activity into their lives. Sallis quickly realized that, although people could often be influenced to adapt their routines to include regular exercise, such changes were rarely permanent, and within six to 12 months people would revert back to their original, unhealthier habits.
This realization led Sallis to the question that would form the foundation of his acclaimed research: what are the root causes of inactivity, and how does the urban environment we live in—and in particular the layout of our cities and neighborhoods—make it easier or more difficult to stay in shape?
A worthy winner
“The role that our physical environment plays in our ability to stay fit is one of the areas of research in the field of active health which has been completely overlooked until very recently, and so we are delighted to honour Dr. James Sallis, whose studies are having a significant impact in helping us understand this crucial link between the built environment and the barriers they present to healthy living,” said Helene Perrault, Dean of McGill’s Faculty of Education.
Dean Perrault says the jury, made up of leading academics from the field of active health, was most impressed by Sallis’s efforts to take his research findings beyond the laboratory and turn them into practical applications. For example, through the Built Environment Assessment Training (BEAT) Institute, he has helped create a free, online course that teaches researchers, policy-makers and others how to assess their local environment—including streetscapes, parks and trails— for physical activity.
Dr. Sallis has also presented his findings to legislators and other policy leaders, including members of the U.S. Congress, First Lady Michelle Obama and former California Governor Arnold Schwarzenegger – part of an effort to affect policy change through evidence-based research.
A renowned, world-class researcher
In addition to his academic appointment at UCSD, Dr. Sallis also serves as the director of the Active Living Research Program, funded by the Robert Wood Johnson Foundation; he has been recognized with numerous honours and awards, including a Distinguished Service Award from the Society of Behavioral Medicine, the Vice Presidency of the American College of Sports Medicine, and a Lifetime Achievement Award from the President’s Council on Fitness, Sports, and Nutrition.
Dr. Sallis will accept the prize at a special ceremony at the MaRS Centre in Toronto on Monday, Jan. 21, 2013, where he will also take part in a conversation about his research. This will be followed by a round table discussion on Wednesday, Jan. 23 at McGill University in Montreal, where local experts will join the prizewinner to explore the topic of the built environment and active health in greater depth.
For those of you who may have missed it on our facebook page, check out this fascinating article from the New York Times health blog:
Can Exercise Protect the Brain From Fatty Foods?
In recent years, some research has suggested that a high-fat diet may be bad for the brain, at least in lab animals. Can exercise protect against such damage? That question may have particular relevance now, with the butter-and cream-laden holidays fast approaching. And it has prompted several new and important studies.
The most captivating of these, presented last month at the annual meetingof the Society for Neuroscience in New Orleans, began with scientists at the University of Minnesota teaching a group of rats to scamper from one chamber to another when they heard a musical tone, an accepted measure of the animals’ ability to learn and remember.
For the next four months, half of the rats ate normal chow. The others happily consumed a much greasier diet, consisting of at least 40 percent fat. Total calories were the same in both diets.
After four months, the animals repeated the memory test. Those on a normal diet performed about the same as they had before; their cognitive ability was the same. The high-fat eaters, though, did much worse.
Then, half of the animals in each group were given access to running wheels. Their diets didn’t change. So, some of the rats on the high-fat diet were now exercising. Some were not. Ditto for the animals eating the normal diet.
For the next seven weeks, the memory test was repeated weekly in all of the groups. During that time, the performance of the rats eating a high-fat diet continued to decline so long as they didn’t exercise.
But those animals that were running, even if they were eating lots of fat, showed notable improvements in their ability to think and remember.
After seven weeks, the animals on the high-fat diet that exercised were scoring as well on the memory test as they had at the start of the experiment.
Exercise, in other words, had “reversed the high-fat diet-induced cognitive decline,” the study’s authors concluded.
That finding echoes those of another study presented last month at the Society for Neuroscience meeting. In it, researchers at Kyoto University in Japan gathered a group of mice bred to have a predisposition to developing a rodent version of Alzheimer’s disease and its profound memory loss.
Earlier studies by the same scientists had shown that a high-fat diet exacerbated the animals’ progression to full-blown dementia, and that both a low-fat diet and exercise slowed the animals’ mental decline.
But it hadn’t been clear in these earlier experiments which was more effective at halting the loss of memory, a leaner diet or regular rodent workouts.
So the scientists set out now to tease out the effects of each intervention by first feeding all of their mice a high-fat diet for 10 weeks, then switching some of them to low-fat kibble, while moving others to cages equipped with running wheels.
A third group began both a low-fat diet and an exercise routine, while the remainder of the mice continued to eat the high-fat diet and didn’t exercise.
After an additional 10 weeks, this last group, the animals that ate lots of fat and lounged around their cages, had developed far more deposits of the particular brain plaques associated with Alzheimer’s disease than the other mice. They also performed much more poorly on memory tests.
The mice that had been switched to a low-fat diet had fewer plaques and better memories than the control group.
But the mice that were exercising had even healthier brains and better memory scores than the low-fat group — even if they had remained on a high-fat diet. In other words, exercise was “more effective than diet control in preventing high-fat diet-induced Alzheimer’s disease development,” the authors write.
Just why high-fat diets might affect the brain and how exercise undoes the damage is not yet clear. “Our research suggests that free fatty acids” from high-fat foods may actually infiltrate the brain, says Vijayakumar Mavanji, a research scientist at the Minnesota VA Medical Center at the University of Minnesota, who, with his colleagues Catherine M. Kotz, Dr. Charles J. Billington, and Dr. Chuan Feng Wang, conducted the rat study. The fatty acids may then jump-start a process that leads to cellular damage in portions of the brain that control memory and learning, he says.
Exercise, on the other hand, seems to stimulate the production of specific biochemical substances in the brain that fight that process, he says.
In the Japanese study, for instance, the brains of the exercised animals teemed with high levels of an enzyme that is known to degrade the plaques associated with Alzheimer’s disease.
Of course, lab animals are not people, Dr. Mavanji cautions, and it’s not known if exercise might protect our brains in the same manner as it does in mice and rats.
Still, he says, there’s enough accumulating evidence about the potential cognitive risks of high-fat foods and the countervailing benefits from physical activity to recommend that “people exercise moderately,” he says, particularly during periods of repeated exposure to alluring, fatty holiday buffets.
The amount of exercise required to potentially protect our brains from the possible depredations of marbled beef and cheesecake isn’t excessive, after all, he continues. His rats were running for the human equivalent of about a daily 30-minute jog. So if you can’t walk away from the buffet table, be sure to at least take a walk afterward.
Let's start off with a simple question: how many sit-ups could you do in 2.5 minutes? 30? 40? Imagine if you did this every morning - would it make a difference? Absolutely, says recent research.
One of the top turn-offs for many people who want to get in better shape is "time", but in a new study, researchers show that exercisers can burn as many as 200 extra calories in as little as 2.5 minutes of concentrated effort a day—as long as they intersperse longer periods of easy recovery in a practice known as sprint interval training.
The finding could make exercise more manageable for would-be fitness buffs by cramming truly intense efforts into very short time persiods. The team at Colorado State University and University of Colorado Anschultz Medical Campus, compared volunteers’ energy expenditures on two different days, one in which they performed a sprint interval workout on a stationary bicycle. Their results showed a marked uptick in the amount of calories the volunteers burned on the workout day, despite the short amount of time spent in actual hard exercise.
Their presentation entitled, “A Single Session of Sprint Interval Training Increases Total Daily Energy Expenditure,” is being discussed this week at The Integrative Biology of Exercise VI meeting in Westminster, Colorado. This popular meeting is a collaborative effort between the American Physiological Society, the American College of Sports Medicine and the Canadian Society for Exercise Physiology.
Study leader Kyle Sevits notes that despite exercise’s numerous documented benefits, few people hit the U.S. government’s recommendations of 150 minutes of moderate exercise or 75 minutes of vigorous exercise per week. “Research shows that many people start an exercise program but just can’t keep it up,” Sevits says. “The biggest factor people quote is that they don’t have the time to fit in exercise. We hope if exercise can be fit into a smaller period of time, then they may give exercise a go and stick with it.”
Though other studies have shown that sprint interval training can markedly improve fitness and athletic performance, little was known about how this type of exercise affects energy expenditure, a factor that motivates many people to exercise.
To determine how many calories a typical sprint interval training workout might burn, Sevits and his colleagues recruited five healthy male volunteers, all between the ages of 25 and 31 years old. These volunteers made an initial visit to Colorado State University in which they performed an exercise stress test to make sure their hearts were healthy enough to participate. The researchers also analyzed the volunteers’ body compositions and their resting metabolic rates.
Over the next three days, the volunteers ate a diet precisely calibrated to meet their metabolic needs so that they’d be in “energy balance,” Sevits explains, with just enough calories so they weren’t over- or under-eating. At the end of those three days, the men then checked in to a research facility at the University of Colorado Anschultz Medical Campus that was outfitted much like a typical hospital room. However, this room was completely enclosed, with air intake and exhaust regulated and equipment installed to analyze oxygen, carbon dioxide, and water content. Based on the results of this analysis, the researchers could determine how many calories the volunteers burned while each stayed in the room.
For two days, each volunteer lived in the room, continuing to eat the prescribed diet and spending the majority of their time in sedentary activities, such as watching movies or using a computer. However, on one of the days, they engaged in a sprint interval workout that involved pedaling as fast as possible on a stationary bicycle in the room that was set at a high resistance for five 30-second periods, each separated by four-minute periods of recovery in which they pedaled slowly with very little resistance. During the intense, 30-second bouts, the researchers coached the volunteers over an intercom system, encouraging them to give 100 percent effort.
Analyzing results from the room calorimeter system showed that the volunteers burned an average of an extra 200 calories on the sprint interval workout day, despite spending just 2.5 minutes engaged in hard exercise. Though the researchers can’t yet speculate on whether such efforts could translate into weight loss, Sevits and his colleagues suggest that engaging in intense, but brief, bursts of exercise could aid in weight maintenance. “Burning an extra 200 calories from these exercises a couple of times a week can help keep away that pound or two that many Americans gain each year,” Sevits says.
However, maintaining the maximum effort needed to exercise at peak intensity over the 30-second sprints could prove tricky for many people to maintain on their own without help, Sevits warns. “Motivating yourself can be very hard,” he says. “The way this could work in the real world is with the guidance of a personal trainer.”
Following a healthy lifestyle can lead to a longer life, even among people who are already well into their 70s, new research shows.
Getting regular exercise, staying engaged with friends and family, and abstaining from smoking were all associated with longer life in a study that followed people in their mid-70s and older for close to two decades.
These healthy traits apparently added, on average, five years to women’s lives and six years to men’s.
The study is among the first to identify specific lifestyle behaviors associated with longer life, even among people with chronic health problems and those over the age of 80, researchers say.
“Our results suggest that encouraging favorable lifestyle behaviors even at advanced ages may enhance life expectancy,” concluded the researchers from Sweden’s Karolinska Institute and Stockholm University.
The study, published in the journal BMJ, included about 1,800 people who were followed for 18 years from the mid-1980s.
Everyone in the study was 75 years old or older at enrollment, and 9 out of 10 (92%) died during the follow-up. Half lived for 90 years or longer, with women being more likely to survive to this age than men. Those who lived longer were also more likely to be highly educated, participate in physical and non-physical leisure activities, have rich social networks, and engage in regular exercise.
Physical activity was the single biggest predictor of longevity. People who regularly swam, walked, or performed other exercise lived an average of two years longer than people who did not. Longevity in former smokers was similar to that of people who had never smoked, but 4 out of 5 former smokers quit between 15 and 35 years before entering the study.
People with the healthiest lifestyles lived an average of 5.4 years longer than those with the least healthy lifestyles. Even among people over the age of 85 and those with chronic health conditions, a healthy lifestyle appeared to prolong life by four years. The study did not include information on diet, so it is unclear how healthy and unhealthy eating behaviors affected life span.
The researchers also didn't know lifestyle behaviors prior to old age. Despite these limitations, Gisele Wolf-Klein, MD, says the findings add to the evidence that it is never too late to improve health and prolong life.
Wolf-Klein is director of geriatric education for the North Shore-LIJ Health System in New Hyde Park, N.Y.
“It has been known for a long time that adjusting lifestyle behaviors at any age can be beneficial in terms of health and survival,” she says. She cites as an example her mentor in geriatric medicine who was a smoker until he had a massive heart attack in his mid-70s. “He gave up smoking ‘cold turkey’ after that and began exercising on a stationary bicycle 30 minutes every day,” she says. “He is still doing it at the age of 94.”
A new study at the University of Copenhagen in Denmark has found that sedentary, slightly overweight healthy young men, who worked up a sweat exercising 30 minutes daily for three months, lost a similar amount of weight and body fat as those who did 60 minutes of daily exercise.
The researchers describe the findings of their randomized controlled trial in a study reported online recently in the American Journal of Physiology.
The researchers suggest one reason for the surprising result is that the exercise felt "doable" for the participants in the 30 minutes a day group, who even felt afterwards that they could have done more. In contrast, the 60 minutes a day group probably compensated by eating more, therefore losing less weight than expected.
This second point would fit in with the results of previous research that the researchers point to in their background information. This suggests that the reason exercise often produces a disappointing amount of weight loss is because a diet-induced negative energy balance (where calories consumed aren't enough to cover daily energy needs) often triggers "compensatory mechanisms", such as lower metabolic rate and increased appetite.
Perhaps 60 minutes of exercise results in more overcompensation than 30 minutes. On average, the men who exercised 30 minutes a day lost 3.6 kg in three months, and those who exercised 60 minutes a day lost 2.7 kg. The reduction in body fat was about 4 kg for both groups.
The result is significant because 40% of Danish men are thought to be moderately overweight. Overcoming barriers to exercise in a group that does none at all should be easier if the aim is to attain 30 minutes a day than 60 minutes a day.
The study is part of an interdisciplinary trial called FINE, a Danish acronym for physical activity for a long healthy life, which has generated strong data in a group of 60 or so participants.
For the study, the researchers randomly assigned each of 62 healthy, sedentary, moderately overweight young men to one of three groups: a high exercise group (burning about 600 kcal per day with about 60 minutes of aerobic exercise), a moderate exercise group (300 kcal per day, 30 minutes exercise), and a control group that continued to be sedentary.
They monitored the men as they followed their program for 13 weeks.The participants trained every day through the study period. The training sessions were planned to produce a light sweat, but the participants were also instructed to increase the intensity three times a week.
The results showed that body weight went down by 2.7 kg in the high exercise group, and 3.6 kg in the moderate exercise group. Fat mass went down by 4.0 kg and 3.8 kg respectively.