Where's Brandan when you need him? I believe he broke his wrist while backpedaling as well.
No backpedaling was emphasised to me because my first games were in a gym with a carpeted floor. It's easy enough to catch a foot on carpet and go down when running forward. Backpedaling on carpet is almost a guaranteed bad experience.
I watched a soccer player do the same thing while running ladders in the gym (early season workout, still too much snow on the field to go outside). He broke his wrist as well. Come to think of it, I never really liked that kid. So it didn't hurt my feelings any that I took his starting spot because of it.