Led by Kinesiology and Health Studies professor Ian Janssen, the new study supports Canada’s Physical Activity Guidelines for Children and Youth, which call for children to accumulate at least 90 minutes of  moderate-to-vigorous physical activity over the course of the day, in bouts of at least five to 10 minutes’ duration. Until now there has been no scientific evidence to support the recommendation of sustained, rather than sporadic exercise.

On a side note, I also noticed that Canadians get a tax rebate for enrolling their kids into fitness programs:

Children’s Fitness Tax Credit (Canada)
Budget 2006 introduced a federal tax credit to promote physical activity among children. Effective January 1, 2007, parents of young people under the age of 16 who register their children in programs that promote physical activity can claim a federal tax credit for up to $500 per year per child on registration fees and memberships.

When a quarter-million Ontario school children were prepping for last week’s province-wide tests in the “3 Rs,” they may have overlooked a surprising study tool.

The workout.

New Ontario research shows schools that push fitness and nutrition have watched their standardized scores rise by as much as 50 per cent over two years in Grade 3 reading and 39 per cent in Grade 3 math – outscoring other schools in similar neighbourhoods by about eight points across all three subjects.

A landmark study of 33 Ontario schools that are part of a health drive called Living Schools – where students exercise each day, play extra sports and are discouraged from eating junk food – saw overall scores climb by 18 per cent over two years in reading, writing and math, compared to about 4 per cent for similar schools not in the provincially funded program.

Principals also said there were fewer fights and better attendance.

The rising incidence of childhood obesity is cause for serious concern, but banning advertising to children is not the quick-fix solution to a multifactorial and complex problem. That was the key message delivered by the Association of Canadian Advertisers at a conference in Ottawa earlier this week examining childhood obesity rates.

In fact, the amount of food and beverage advertising directed to children has been decreasing in recent years even as obesity rates have climbed, Bob Reaume, the ACA’s Vice President of Policy and Research told the conference, held in response to a report on childhood obesity released last year by the federal government’s Standing Committee on Health.

Reaume’s comments stood in sharp contrast to those of a panel, comprised of academic and community representatives, who claimed a causal link between advertising and obesity. The panel is calling on governments to impose a marketing ban on “unhealthy” food and beverages to children.

Reaume noted that industry is taking a proactive approach to the obesity problem by pledging only to advertise healthier choice products and healthy active living messages. Marketers are eager to collaborate with policy makers and health groups to find effective solutions.

The study suggested that the impact of a neighbourhood’s poverty level rather than affluence may matter most in a child’s weight. It is possible that neighbourhoods may become more important as children age and have more freedom to access the neighbourhood. It is also possible that disparities emerge over time, as children are exposed to such environments over a longer period.

This got me thinking. Why would families on low-income be more likely to overweight and obese? Perhaps it’s simple economics: A family will try to maximise the amount of energy intake for the least cost possible - in other words more calories per dollar. If you spend a greater proportion of money on food, then you are sensitive to this equation. Apparently, I’m not alone with this opinion:

Healthy eating really does cost more.

That’s what University of Washington researchers found when they compared the prices of 370 foods sold at supermarkets in the Seattle area. Calorie for calorie, junk foods not only cost less than fruits and vegetables, but junk food prices also are less likely to rise as a result of inflation. The findings, reported in the current issue of the Journal of the American Dietetic Association, may help explain why the highest rates of obesity are seen among people in lower-income groups.

The scientists took an unusual approach, essentially comparing the price of a calorie in a junk food to one consumed in a healthier meal. Although fruits and vegetables are rich in nutrients, they also contain relatively few calories. Foods with high energy density, meaning they pack the most calories per gram, included candy, pastries, baked goods and snacks.

The survey found that higher-calorie, energy-dense foods are the better bargain for cash-strapped shoppers. Energy-dense munchies cost on average $1.76 per 1,000 calories, compared with $18.16 per 1,000 calories for low-energy but nutritious foods.

The survey also showed that low-calorie foods were more likely to increase in price, surging 19.5 percent over the two-year study period. High-calorie foods remained a relative bargain, dropping in price by 1.8 percent.

Although people don’t knowingly shop for calories per se, the data show that it’s easier for low-income people to sustain themselves on junk food rather than fruits and vegetables, says the study’s lead author Adam Drewnowski, director of the center for public health nutrition at the University of Washington. Based on his findings, a 2,000-calorie diet would cost just $3.52 a day if it consisted of junk food, compared with $36.32 a day for a diet of low-energy dense foods. However, most people eat a mix of foods. The average American spends about $7 a day on food, although low-income people spend about $4, says Dr. Drewnowski.