Dr. Obvious nearly choked on his own laughter when he called to tell me about a new study by researchers at Cambridge University that concluded kids who walk to school are less likely to be obese than those who travel by bus or car. But there are some interesting sidebars to the tale…
Kids who play sports may have higher BMIs than kids who don’t
but that doesn’t necessarily mean they’re obese…
What they did
The investigative team looked at the health and habits of 2,000 primary school students from across Greater London, seeking to0 determine, “the impact of physical activity on childhood overweight and obesity levels for primary schoolchildren by simultaneously relating two of the main types of extracurricular physical activity: daily commuting to school and frequency of participation in sport.”
Rather than using Body Mass Index (BMI), the usual measure of obesity, researchers measured both body fat and muscle mass to determine hjow these factors corellated with physical activity levels.
“Both BMI itself and the points at which high BMI is associated with poor health vary with age, sex and ethnicity,” said Dr. Lander Bosch, the study’s First Author. “While adjustments have been made in recent years to account for these variations, BMI remains a flawed way to measure the health risks associated with obesity.”
What they found
Kids who ‘actively commuted’ to school every day – that is, walked, rode bikes or used scooters or skateboards – had less body fat and were less likely to be obese. Oddly, kids who did at least one sport regularly appeared to be prone to obesity. But that was just a surface perception; the kind of error that can occur when observers rely on BMI data only. In fact, kids who did sports were found to be more likely to have greater muscle mass than kids who didn’t but their body fat levels were comparable.
“The link between frequent participation in sport and obesity levels has generated inconsistent findings in previous research, but many of these studies were looking at BMI only,” said Bosch. “However, when looking at body fat instead, we showed there was a trend whereby children who were not active were more likely to be overweight or obese.”
Dr. Obvious had to pause to compose himself at this point.
The takeaway
“Our findings suggest that interventions promoting regular participation in sports, and particularly active commuting to school could be promising for combating childhood obesity – it’s something so easy to implement, and it makes such a big difference,” said Bosch.
My take
Isn’t this something we’ve known for years? That people – and not just kids – who are more active are less likely to be obese? Not to mention that active people tend to be stronger and have healthier hearts? The real finding of the new Cambridge study seems to be that, as researchers postulated, looking at BMI alone may not be a valid measure of obesity. But to say that the study revealed something new and surprising about obesity is, in short, a giggler.
However, I have to note that it’s much less likely than it used to be that kids today are walking to school. Protective parents and the many evils that can befall kids between home and classroom – not to mention the policies for mixing kids from different socioeconomic strata by busing them around to schools that might not be the closest to their homes – has made walking a thing of the past for the majority. Perhaps the message we should be getting is that that kids need more extracurricular activity to make up for their lost walking exercise.
Dr. Obvious walks two or three kilometres every morning and recommends it highly. If you find that a difficult commitment to make, he recommends you get a dog. (See photo top of page.)
~ Maggie J.