I am an upcoming senior HS football player at 5'8 170-175. I have been doing sprinting for our conditioning program for about a month now and I still struggle though them. I usually find myself out of breath, tired, and sometimes lightheaded by the end of the session. I NEVER quit during a session and fight through despite my actual body's feelings. Any advice? Also, what would be an efficient diet guideline for me to help maintain my weight with all the running I do?