I had a knee injury from running and had to see a physical therapist. While my pt was great, I left to go abroad for 3 months afterwards and found it difficult to continue my therapy on my own. There's a new app out for the iPhone and Android that is basically a physical therapist in your pocket. It's a free app and you can customize the exercises you want to do. I chose knee, strengthen, running and it gave me a customized list of all exercises I can do with videos and voice-over. I want to spread the word so other people won't have the same problem I had! Now I always use this app at the gym when I run. It's a great tool for anyone who wants to treat or prevent injury! It's called FORCE Mobile and you can get it in the app store or at forcemobile.net