There isn't one specific muscle or group of muscles that you should work on. Basketball requires just about all of them. Now if you're talking about adding to your vertical leap, that involves calves, quads and hamstrings. Best way to do that is squats, plyometric boxes and jumping rope. But what I do personally and have my team do is full body strength training workouts. You need strong shoulders, back, arms, abs and chest just as much as legs. Plus add a good deal of cardio work in there for endurance. Hope that helps some.

The one thing, and most important thing that Coach Vanek didn't mention is core strength. The large muscle groups are important, but the stabilizers are also important, especially for preventing injury (ask Shaq about his hip flexor).

In conjunction with everything else you should be working on core strength exercises to reduce physiological imbalance. You should also focus on the stabilizing muscles of your ankles, knees, and hips, all to often those are neglected and serious injury can occur.

The best piece of equipment for lower joint stability work would be the Bosu ball.

calf