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Why Do I Feel Hungry After Workout?

You are not alone if you've ever completed a workout and then had the need to stuff your face instantly. Post-workout hunger pangs are a real problem that impacts some gym-goers from time to time.

Why Do I Feel So Hungry When I Work Out?

Since hitting the gym, there are some reasons you may feel like you could eat a horse. The first: you have already starved into the exercise. "A lot of people go through undernourished exercises and become ravenous," says licenced dietitian Maya Feller. But how does it work, exactly?

Well, when you work out — or, for that matter, do some sort of movement — your body uses a material called glycogen to fuel the motion. Your body gets glycogen from carbohydrates — basically, as you eat carbs, the body cuts them up into glucose and preserves them as glycogen, says dietitian Tanya Zuckerbrot.  Your liver secretes hormones ghrelin when you use up your glycogen reserves, which signals your brain it's time to munch.

If you participate in a workout with already-low glycogen stocks, exercise could further deplete them and cause ghrelin release. If your glycogen stocks are very poor, that can translate into that sensation that I-need-to-eat-something-ASAP.

Dehydration is another potential cause for post-exercise pangs of hunger. You lose water while running and sweating, and hence suffer symptoms of dehydration.  Since dehydration symptoms are close to that of hunger — such as feeling exhausted and shaky — you may quickly connect the two. For that reason, Zuckerbrot defines that not drinking enough H2O before, after and/or after a sweat session can cause hunger-like symptoms. In other words, you might think we're super hungry for a sweat sesh, when you're really dehydrated, really.

Finally, working out really intensively and/or for a long time will cause extreme feelings of hunger, even though you went into the exercise well-hydrated and well-nourished, but this is not something that the general public of gym goers wants to care about.

For the average person who workouts regularly a few days a week, hunger after a workout shouldn't be so serious that you feel faint if you don't catch something to eat right afterwards," says registered dietitian Alyssa Pike.