What a runner eats after a run is as important as what he/she eats before a run. Eating a meal before a run will give you energy to fuel your run while eating after a run will help you in replacing spent energy.
Jeff Galloway a Long distance Running coach stresses why runners need to bite something after a race.
Foods to eat after marathon running
“After you finish running, you should always try to eat something within 20 to 30 minutes. The latest research that Jeff has seen suggests eating about 200-300 calories immediately following your long run that is made up of 80% simple carbs and 20% protein. This will best aid you in recovering your spent muscle glycogen. You should also continue to eat throughout the day to restore most of the calories that you burned, but that 200-300 calories will do the most good within half an hour of your workout.”