The Science Behind Eating After a Long Run

Posted by Sam on March 28th, 2021

Workouts can temporarily reduce appetite. Research shows that long runs, continuous aerobic exercise, cause the greatest short-term reduction in appetite.

The “I am hungry” hormone DECREASES after a long run

Ghrelin, recently renamed by me as the “I am hungry” hormone, is always suppressed when you perform continuous aerobic exercise. In the few hours after your long run, your body and mind will be telling you that “I am hungry” less.

The “I am not hungry” hormone INCREASES after a long run

Long runs also stimulate an increase in peptide YY, what I refer to as the “I am not hungry” hormone that seems to last for some time after your continuous aerobic workouts. This will also trick your body and mind but in the case of this hormone, you will be told over and over again that “I am not hungry.”

What does this mean?

Barry Braun, PhD, professor of kinesiology and director of the Energy Metabolism Laboratory at the University of Massachusetts in Amherst, chimes in:

“In the short term, during or right after a workout, exercise may suppress hunger… But later that day, your hunger hormones can surge, making you want to eat. At the same time, your body’s satiety hormones, the ones that signal that you’re full, may decrease.”

Do Not Fall For The Traps

In nearly all situations, it is usually best to listen to your body and mind. With regards to this feeling of fullness after running long distance, do not listen.

Trap 1 – You temporarily lose sight of the big picture. You may get all excited that you just burned a bunch of calories and even more pumped up that you are not that hungry. You think it is in your best interest, especially if you are trying to improve your body composition, and then the immediate effects of appetite suppression after your long run disappear. You end up eating more bad stuff/less good stuff than you had planned.

Trap 2 – You are thrilled with your finished workout that you temporarily forget that you need to start preparing yourself for your next workout. You skip your post-workout liquid nutrition and/or post-workout snack/meal. You take longer to recover for your next workout. And then your next workout suffers.

Force Yourself to Eat After Running

Post-workout nutrition plays a significant role in your ability to stick to your nutrition plan and maximize your running performance. Eating well after your long run, and all other workouts, will improve your body composition. 

What to Eat After a Long Run

What to eat right after a long run depends on a number of factors including your current fitness level, your specific goals, your food preferences, etc. As you probably know, if you read this blog regularly, I believe in customizing everything to the exact specifications of the individual athlete. I do this with all of my run training and nutrition programs that I customize for runners. 

For the purpose of this article, here are some general tips on what to eat after a long run:

What to Eat Immediately After Your Long Run

Eat a Liquid Meal

What to Eat a Few Hours After Your Long Run

Eat Solid Food

By eating right after you workout, you will have more control over what you eat the rest of the day and will be fresher in your next workout to continue to progress towards your goals.

You may not be hungry right after your run, but eat anyway and maximize your recovery, body composition and performance.

The reason many runners struggle with dropping body fat is because they do not eat right after they workout. This leads to more of a caloric intake (eating unhealthy food later in the day) and less of a caloric expenditure (sabotaging the quality of the next hard workout). And we all know that a low body fat percentage, as long as it is in the healthy ranges, is directly related to running success. 

Warning: Men will have more of a suppressed appetite after a workout than women.