I got injured at the end of last track season with a stress fracture the day after a 1500 where I ran 3:52. I took 6 weeks off where I wasn't motivated to do much cross training except a 20-30 mile bike ride 2-3 times per week. Now that I am back running and fully healed, I am feeling VERY out of shape compared to where I was at before. How long before I have regained all my fitness that I have lost?