If exercising on an empty stomach just sets you up to eat more later in the day than you would have if you ate before running, then there is no benefit.Also consider the fact that a small snack before may allow you to exercise harder and run longer, which would result in burning more calories.
Accordingly, do you eat before or after you run?
When you begin a run, you should feel neither starved nor stuffed. But running on an empty stomach may cause you to run out of energy and leave you feeling very fatigued during your runs. Your best bet is to eat a snack or light meal about 1 1/2 to 2 hours before you start running.
When should you eat before a run?
In general, wait two to four hours before running after eating a large meal. This allows time for your food to fully digest. After a smaller snack, 30 minutes - two hours should be sufficient, depending on how much you have eaten.
When should you eat after a run?
Studies have shown that muscles are most receptive to rebuilding glycogen stores within the first 30 minutes after exercise. If you eat soon after your long run or intense workout, you can minimize muscle stiffness and soreness. You'll want to consume primarily carbs, but don't ignore protein.