Both of my kids are in track, and their coaches seem to emphasis proper nutrition much more than my track coach did when I was in high school.
I do remember our coach encouraging us to get a good night of sleep before a meet and to drink plenty of water. That is about the extent of our coaching on nutrition and fitness.
The track and field coaches that my kids have emphasize that, but also talk more about the specific kinds of foods they need to eat. They encourage them to eat healthy fresh fruits and vegetables.
They also try to get them to limit the junk food and amount of soda they consume. I think all of these suggestions are great reminders for them.
If you have proper nutrition, you will be able to perform better, and have better stamina.