I'm in the Navy so i know what you're going into with boot camp. You'll probably want to change your diet to something healthier. Try looking that up online, but basically I'd make sure to cut back or all the way on candy and soda. You don't need that junk anyways. Drink water, you'll learn how much it can do for you when you finally get into boot camp.
Make sure to go to all the DEP meetings and take the PT seriously. they'll teach you for what the Navy is going to want you to do and that workout will get you down to size, especially mixed with a good diet.
Work hard at being fit, it'll help you out with advancement for years to come. Don't forget that if you're current going in as an E-1, if you can pass your written test (which I'd easy if you do any studying) and pass your first physical assessment, you'll get promoted to E-2. Which is a extra nice considering that E-1s have an additional pay hit for being new E-1s. Good luck, keep running, and I hope to see you in the fleet.