Obesity Studies Weak Without Fitness

important is fitness in studying obesity cases? Very, according to professor Steven Blair of the Arnold School of Public Health at the University of South Carolina. Blair argues that that the government's focus on obesity has sidelined the importance of fitness; his research shows that fitness can trump obesity, and that moderately fit obese people have nearly the same prospects as thin people.

Blair discussed with National Journal the importance of recognizing fitness when looking at obesity.

NJ: Are we gaining weight because of modern conveniences such as elevators, air conditioning, etc.?

Blair: The major cause of the obesity epidemic has been declining levels of energy expenditure brought about by all sorts of modern conveniences at home, at work, etc. Now, that's my opinion, because we have never seen fit to actually collect really good data on energy balance to know which side of the energy balance equation is really driving the weight gain. So I don't see how we'll ever get effective strategies for dealing with it until we nail [it] down a little better. Is it increased intake or decreased expenditure? I put my bet on the latter.

NJ: How useful are the studies of a population's obesity if those studies do not examine the fitness of heavy people?

Blair: I think any research that purports to examine overweight, obesity, fat distribution and any health outcome that fails to measure physical activity objectively, accurately or measure fitness accurately -- if they don't do that, it's junk science. And you should just simply ignore it. Because in studies such as ours, where we have objective measures of adiposity and fat distribution, an objective laboratory test of fitness, when we look at fatness and mortality and adjust for fitness, it eliminates the association between fatness and early mortality, mortality from cardiovascular disease, a wide range of health problems. We've got to study these two things equally or it's junk science. I would never submit a paper on activity or fitness and any health outcome without at least height and weight, if not measures of adiposity.

NJ: Why are the fitness companies apparently uninterested in marketing fitness to older and heavier people?

Blair: I'm a little amazed by that [laughs]. The fitness companies seem to focus their attention on the younger, the fit, the athletes. You know, there are an awful lot of people in my generation who could benefit from being more active. And you occasionally see a little interest from the fitness companies, whether that's shoes or equipment and the like. I'm a little surprised that they aren't more actively engaged in a public health effort to promote physical activity and fitness for people of all ages.