Does Exercise Really Help with Weight Loss?
For a long time, the weight loss mantra has been to eat less and exercise regularly and often, yet the epidemic of overweight and obesity not only continues but is growing. A provocative article in the Sunday, August 9 issue of Time entitled “Why Exercise Won’t Make You Thin” draws attention to a part of the mantra that may be in error: exercise may not really help achieve weight loss.
While the Time article makes several points about the failure of people to achieve weight loss through exercise, one truth shines through: when people exercise, they tend to either (1) reward themselves with food - often fattening food - for their efforts; and (2) exercise makes people hungry, so they are more likely to eat. As quoted in Time, Steven Gortmaker, head of Harvard’s Prevention Research Center on Nutrition and Physical Activity, “If you’re more physically active, you’re going to get hungry and eat more.” People who are hoping that will power will save them from gaining weight are likely fooling themselves. According to an article in the journal Psychological Bulletin, psychologists Mark Muraven and Roy Baumeister noted that like a muscle, self-control grows weaker after you use it.
In a 2008 article published in the British Journal of General Practice, the authors hypothesized that given the limited success with any weight loss strategies exemplified by the obesity epidemic, when dieting attempts have failed, it may be better to strive for weight stability. That is, doctors and patients may do better to ensure any weight loss is maintained and to take steps to maintain a person’s existing weight without attempting weight loss.
One way to do this is to encourage exercise, which is known to benefit the cardiovascular system, reduce stress, improve mental status, and other overall health benefits. Therefore rather than the pressure to exercise vigorously to lose weight, which has not been successful for many people, the emphasis would be on preventing further weight gain, protecting any weight loss that has occurred, and promoting overall wellness.
A recent study from the University of Colorado Denver’s School of Medicine reports that exercise helps prevent weight regain after people have had successful weight loss by reducing their appetite and burning fat before it burns carbohydrates. When the body burns fat first and stores carbohydrates for later use, this process slows weight gain and may limit the amount of overeating by sending messages to the brain that the stomach is full.
The same scientists found that exercise prevents the increase in the number of fat cells that develop during weight regain, a concept that challenges the conventional wisdom that the number of fat cells is set in stone and that people cannot change them through diet or exercise. Therefore, although exercise may not promote further weight loss for some people, at least it can prevent more fat cells from being produced.
So does exercise really help with weight loss? For some people it may; for others, it may be the tool they can use to maintain any weight loss they have already achieved. It certainly has been proven that exercise, separate from helping people lose weight, offers many other crucial health benefits, and if only for that reason, people need to engage in regular, moderate exercise, including walking away from the refrigerator and the fast food restaurants and pushing away from the table.
Cloud J. Time September 6, 2009
MacLean PS et al. American Journal of Physiology, Regulatory, Integrative and Comparative Physiology 2009 Sep; 297(3): R793-802
Muraven M, Baumeister RF. Psychological Bulletin 2000 Mar; 126(2): 247-59
Pryke R, Docherty A. British Journal of General Practice 2008 Feb; 58(547): 112-17