Diet is #1, so if you eat right you have the building blocks.
Exercise is next and you don't need traditional weights to do it, your body is essentially a weight. Break dancing incorporates a ton of moves you simulate in the gym push-up's, spins, etc, all use yur body weight being supported by certain muscle groups. The amount of control in many break dance moves, requires a lot of core strength in order to perform them properly.
You can get a full workout without weights at home, so why not act like a robot while you are at it.
Dancing alone is a great cardio routine, I can only imagine how much time he spends practicing his moves etc. I am a personal fan of Stalls, the control and muscle required to do them always make my jaw drop.