Does Running Make You Lose Your Appetite?

You know fueling is important after a run, but you have absolutely no appetite. In the immediate post-run period, your urge to eat may be nonexistent. After a few hours of rest, your hunger levels do return to normal. Loss of appetite can be a temporary side effect of running. In the long term, running and other aerobic exercise may make you hungrier rather than permanently reducing your urge to eat.

Right after a vigorous run, your appetite is lacking because of a temporary rise in body temperature. A study published in the May 2012 issue of the "Journal of Applied Physiology" found that when participants completed 60 minutes of intense exercise, they experienced reduced activity in the brain regions that correlate food with pleasure and provide the motivation to eat. The researchers from California Polytechnic State University concluded that the reduced activity in this brain region suppressed immediate energy intake after a vigorous workout. An hour run would definitely qualify as intense exercise that could lead to this dip in the desire to eat.

When your body temperature returns to normal -- after a few hours -- your appetite may actually increase. When you run, you burn a significant number of calories and your body’s hunger sensors go into overdrive to replace them. The run can also have the effect of making you feel as if you “earned” extra calories, so you are less likely to turn down an extra helping at dinner or a sweet treat at snack time. Increased appetite and feelings of entitlement can interfere with the weight management or weight loss benefits of exercise.

Reduced appetite immediately after a run can affect post-workout fueling. Registered dietitian Leslie Bonci told “Running Times” that athletes should consume a snack containing carbohydrates and protein as soon as possible after a run to help with recovery. She advocates your meal come within 15 minutes of stopping. If you have no appetite, this refueling can be challenging. Opt for a snack with a ratio of 3-to-1 or 4-to-1, carbohydrates-to-protein. A smoothie or specially formulated carbohydrate-protein drink may be more tolerable if you simply cannot stomach the idea of whole foods. You need the carbs to replenish depleted energy stores and the protein to help with the repair of fatigued muscles. If you skip this post-workout meal due to poor appetite, you'll take a longer time to recover.

Don't skip running just because it interferes with your appetite. A regular running program, like any exercise system, offers numerous benefits, such as increased stamina, improved heart health and, possibly, a commitment to a better diet. Once your initially suppressed post-run appetite returns, opt for healthy foods such as whole grains, fruits and vegetables, lean proteins and low-fat dairy for satisfaction.