Q. Does aerobic exercise suppress a person's appetite? Some experts say it does, others say it doesn't. Who's right?
A: The vast majority of studies have demonstrated that caloric intake is usually unchanged or slightly increased in response to long-term aerobic exercise training.
Energy intake is, however, usually increased below the level of the increase in energy expenditure. This situation results in a negative energy balance (i.e., energy expenditure > energy intake) and, concomitantly, a loss of body weight and body fat.
Some evidence exists, however, that if you vigorously exercise before you eat, you will actually eat less because of an increase in your body temperature and an alteration in your hormone levels.
Keep in mind that the centers for the thermoregulatory system, appetite, and sleep lie right next to each other in the brain stem. When you affect one, you will likely affect the others.
Source: Bryant, Cedric X. 101 Frequently Asked Questions about "Health & Fitness" and "Nutrition & Weight Control". Sagamore Publishing, 1999.
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