You might not actually work up an appetite while exercising. A new study shows that a brisk morning workout may reduce a person's desire for food.
Researchers from Brigham Young University (BYU) used electrodes to measure the neural activity of 35 women while they looked at pictures of food on two different days. On one day, the women had spent 45 minutes of their morning exercising, while on the other day, they did not exercise.
The researchers found that after exercising, the participants' attentional response to the food images dropped. Throughout the rest of the day, women who had worked out also showed an increase in total physical activity, regardless of body mass index. (About half of the women in the study were obese.) And the women did not eat more food on the exercise day to "make up" for calories burned in the workout, the researchers said. Rather, the participants consumed about the same amount of food as on the non-exercise day.
The researchers said more work is needed to determine how long these effects last and whether long-term exercise has any impact on a person's motivation for food.
The study, now online, will appear in the October print issue of the journal Medicine & Science in Sports & Exercise.