No one likes to be slowed down by an injury, but they do unfortunately happen. You do not, and really should not, stop moving completely because the injured area and the rest of your body can begin to atrophy – losing both muscle mass and strength, as well as range of motion.
If you have strained or pulled a muscle or sprained your ankle, you know exercise plays a role in recovery. As soon as possible, after injuring yourself you should follow the R.I.C.E. procedure: rest, ice, compression, and elevation. Do consult with your physician or a physical therapist if the injury necessitates it.
When you begin to work out again, pay attention to how the injured area feels. Discomfort is OK, but pain is an indicator to stop. With most injuries, getting the area moving quickly after the injury actually speeds up the healing process. For example, if you have twisted your ankle, within a day or two of hurting yourself try drawing the alphabet with your big toe – as long as the motion doesn't cause pain. When you are able, you want to proceed with weight-bearing exercises, too.
Working those injured areas reminds me of that expression about "getting back on the horse." And not to "beat a dead horse," but you do know the best way to avoid sports injuries is properly warming up.
Get out there! Have fun! Play safe!