well, you can do most cardio...swimming, running, eliptical, biking. You can life for legs. If you have a gym membership, you can hit the leg machines and you won't need your arms at all. You can also do most of your ab work as well. The only thing that should suffer is your upper body lifting and your striking/grappling. Just goes with the territory of getting injured. Watch some technique vid or read a technique book. You can at least shadowbox while you're waiting to heal.