Working Up an Appetite? Not!

Moderate to vigorous exercise helps lower hunger

(RxWiki News) Working out and exercise is supposed to help build an appetite, right? That may not be the actual case.

A recently published study found that 45 minutes of moderate to vigorous exercise actually lowers a person's desire for food.

"Being active keeps food cravings at bay."

Though the study was small, Bliss Hanlon, a former graduate student at Brigham Young University, and colleagues measured the brain activity in 35 women while they looked at images of food.

Half were normal weight and 17 were clinically obese.

Researchers attached electrodes to the participants' scalps to measure their neural activity. The participants were instructed to record what they ate and how much physical activity they had on experiment days.

On the first day of testing, participants walked on a flat treadmill at about 4 mph for 45 minutes.

Researchers measured participants' brain waves with an electroencephalogram as they looked at 240 images of plated food and flowers, which helped keep the experiment focused on food.

The same experiment was done a week later at the same time of the morning without exercise.

Researchers found their brain waves were smaller when viewing the pictures after the brisk workout, meaning that the participants paid less attention to the pictures.

The women did not eat more food on the exercise day to "make up" for the extra calories they burned in exercise, the authors said in a press release. They ate about the same amount of food on the non-exercise day.

“We wanted to see if obesity influenced food motivation, but it didn’t,” Dr. James LeCheminant, PhD, an exercise science professor at BYU, said.

“However, it was clear that the exercise bout was playing a role in their neural responses to the pictures of food.”

The authors said more research needs to be done to figure out how long after exercise the food motivation stays low and what would happen with long-term, persistent exercise.

Funding information and whether the authors had any limitations in their study is currently unavailable.

The study was published online May 22 in the journal Medicine & Science in Sports & Exercise from the American College of Sports Medicine.

Review Date: 
September 15, 2012