Grade: 2
A few damaged fibers in the semimembranosus. I am not sure how it start. I felt that the region was tender after the Tiomila, but I thought it was only some normal soreness. Than 3 days later I wanted to do 200m intervals on the track, but from the first step it hurt enough that I had to stop the training.
When a muscle is not functioning properly and hurts clearly. Take a total rest, and start running until the physio says it is ok... in this case I actually thought it wasn't good yet... but the physio was right.