I got a good firm one at a Walmart for like fifteen bucks to keep in my locker, in my car, whatever. I love a good foam roller, before and after workouts I'll roll. For lower body days, I do hamstrings, each glute, calves, quads, IT bands(A good HURT), and groin(making sweet love to the foam roller). For upper body days I do upper and lower back, and traps. I tend to add extra focus on the areas that are really sore. During fall camp I would roll everything before practice, and did the same before games. They're a life line man.