I'm going to be joining an army soon, and want to be as prepared as possible.

I'd like to know what the best workouts are for these areas:

1) Sprints. I'll need to be able to sprint for all of the tests in order to get into the unit I want. Obviously, I need to practice sprinting. But, what other workouts can really help improve me sprint times and stamina?

2) Hikes. I'll be doing a lot of hiking. Currently, I am running up steps and squatting. What other workouts should I do to improve my leg strength and stamina?

Thanks for any help provided!