I am a cross country runner. What should I be eating during the day?

If you feel like crap after eating McDonald's or Wendy's, then I suggest stop eating it. Try eating a sandwich, bagel, and/or banana and drink a lot of fluids. Find something that you can eat and leave you feeling good for practice. Once you find that, keep eating that and make it into a routine. That will insure you always feeling good for practice and meets.