As a sprinter, you probably don't get enough long steady state runs. These runs help distance runners keep a fast metabolism and burn enough calories.
My suggestion would be to incorporate an Atkins-like diet. By this I mean, avoid bad carbs like sugars and white starches (potatoes and fries). Also, avoid bad fats aka saturated or trans fatty acids. That's the bad news.
The good news is you can enjoy lean cuts of chicken, pork, or beef. If you're a vegatarian, indulge in legumes, soy, and chickpeas (also a bean).
Do not skimp on fiber. This is vital and a missing component of the Atkins diet. Legumes, wheats, nuts, vegetables, and some cereals are great sources of fiber. Fiber will also make you feel fuller, and eventually leave the system anyway.
The overriding theme is stay away from bad carbs and bad fats. Increase intake of protein and fiber. It's my shit-yourself-thin formula.
Also, remember to treat yourself.
Hope this helps.