Researchers measured the brain activity of 35 women while they looked at 240 images—half were of food, and the other half flowers. The first measurement took place right after 45 minutes of brisk walking on a treadmill; a week later, the same neural activity was measured but without the exercise. The results found that the morning workout led to lower brain responses to the pictures of food.
Interestingly, scientists also found that participants ate roughly the same amount of calories on both days, regardless of exercise. The 45-minute workout also led to an increased amount of physical activity throughout the day.
Can We Trust It?
For starters, the workout in this experiment was 45 minutes of treadmill walking, leaving us wondering if food cravings would increase with more rigorous or sustained exercise. (Half-marathon or interval training, anyone?) Moreover, the study measured brain activity directly after working out, failing to address the question of how long a lack of food motivation may last.
Yet, this experiment does question whether it’s smart to fill up on food immediately after working out, which can lead to unnecessary weight gain (if we overdo it). It’s important to consume a good balance of carbs, protein, and fat after a workout to aid in recovery, but it’s just as important to listen to our bodies to really check hunger-level Contemporary Issues in Protein Requirements and Consumption for Resistance Trained Athletes. Wilson, J., Wilson, G. California State University East Bay, Hayward, CA. Journal of the International Society of Sports Nutrition. 2006; 3(1): 7–27.
What to do, then? Skip the stack of pancakes and enjoy a healthy post-workout snack (like a protein shake!) to refuel the right way.