Also balance is the foundation of human movement. Balance is a great thing to get during the summer. You will get stronger faster when you start lifting weights later, and you will be more explosive because you will be able to direct force in the direction desired given great balance! So a BOSU ball is best too to add in to the bodyweight circuits with lunges, squats, step ups, etc.
Just some thought since your new to college track!
someone tell me i didnt just read that……