As a dancer, I have experienced injury, and I have witnessed the nasty injuries of others first hand. If you are heavily involved in sports, chances are that sooner or later you are going to get hurt. The most detrimental thing you can do if it happens to you? Ignore your doctor's advice.
When we are in a cast, on crutches, or just clutching the IcyHot to a sore muscle, we tend to push our bodies a little too hard. Active, ambitious people - often found in the world of sports and dance - have trouble sitting still. It mentally hurts them more than the physical injury is causing them strife!
However, while it is admirable to push yourself on the playing field, pushing your body when it is injured is just plain stupid. Stressing a muscle too soon or attempting to push through pain for the sake of the game is rarely a good idea.
Follow the doc's orders and rest up! In the long run, this is the best thing you can do to quickly get back on your feet. And don't fret, those in shape often heal much more quickly than a usually idle lifestyle.