SCIENTIFIC PROOF LIFE IS NOT FAIR!

I loved the twists in the article I read in the NY Times about diet and exercise.  There has been some question about just how valuable exercise is when dieting.  Mostly because exercise at the level most of us actually participate, we just doesn't burn that many calories.

“In general, exercise by itself is pretty useless for weight loss,” says Eric Ravussin, a professor at the Pennington Biomedical Research Center in Baton Rouge, La., and an expert on weight loss. It’s especially useless because people often end up consuming more calories when they exercise.

“The body aims for homeostasis,”wrote Barry Braun, an associate professor of kinesiology at the University of Massachusetts at Amherst, in the American College of Sports Medicine’s February newsletter. It likes to remain at whatever weight it’s used to. So even small changes in energy balance can produce rapid changes in certain hormones associated with appetite, particularly acylated ghrelin, which is known to increase the desire for food, as well as insulin and leptin, hormones that affect how the body burns fuel."

Here's where it gets unfair:

In physiological terms, the results of one study “are consistent with the paradigm that mechanisms to maintain body fat are more effective in women,” Braun and his colleagues wrote. In practical terms, the results are scientific proof that life is unfair. Female bodies, inspired almost certainly “by a biological need to maintain energy stores for reproduction,” Braun says, fight hard to hold on to every ounce of fat.

On the other hand, if you can somehow pry off the pounds, exercise may be the most important element in keeping the weight off. “When you look at the results in the National Weight Control Registry,” Braun says, “you see over and over that exercise is one constant among people who’ve maintained their weight loss.”


At least the very latest science about exercise and weight loss has a gentler tone and a more achievable goal that the study that came out suggesting women needed vigorous exercise an hour a day, every day to maintain weight. “Emerging evidence suggests that ­unlike bouts of moderate-vigorous activity, low-intensity ambulation, standing, etc., may contribute to daily energy expenditure without triggering the caloric compensation effect,” Braun wrote in the American College of Sports Medicine newsletter.

In a study Braun just completed in his energy/metabolism lab, volunteers spent a day sitting and then a day standing.  The volunteers who stood all day not doing anything in particular, metabolised  a significant number of calories without triggering their appetite hormones.  So you don't necessarily have to get on a treadmill, just get off the chair more!