Gretchen Reynolds has a nice piece today on the diet vs. exercise schism that many of us come to terms with on our weight loss journeys. Citing two new pieces of research (one of which has already been covered here), she notes how research continues to suggest that exercise is a minor contributor to weight loss (compared to diet) and that the oft cited adage that that is frequently invoked to promote weight loss (“Exercise speeds up your metabolism which increases weight loss”) isn’t really all it’s cracked up to be when scrutinized:
One of the few studies ever to have scrupulously monitored exercise, food intake and metabolic rates found that volunteers’ basal metabolic rates dropped as they lost weight, even though they exercised every day. As a result, although they were burning up to 500 calories during an exercise session, their total daily caloric burn was lower than it would have been had their metabolism remained unchanged, and they lost less weight than had been expected.
So much for the increased metabolic effects of exercise… Looking forward to reading the actual studies referenced by Reynolds (currently only an abstract is publicly available for the second one). Let’s see if these results from it can be reproduced.
- Dieting vs. Exercise for Weight Loss, Aug 1, 2012. Gretchen Reynolds, New York Times.
- Those Mythical Hunter Gatherers Who Stay Thin Because They Are More Active Than You? July 27, 2012. Ketopia.
- Do I Need To Exercise To Lose Weight? Feb 27, 2012. Ketopia.
- Why do individuals not lose more weight from an exercise intervention at a defined dose? An energy balance analysis. (abstract) July 11, 2012. Thomas D, Bouchard C, et al. Obesity Reviews.
- Hunter-Gatherer Energetics and Human Obesity, Pontzer, Raichlen, et al. July 25, PLoS ONE 7(7): e40503. doi:10.1371/journal.pone.0040503