I’m 17 years old, I started doing serious training about 3 years ago. I do 2 times a week weight training, I just do the basic things like benchpress, squat, leg curl, straight leg deadlift, pully, biceps, clean. In the winter I do a lot reps and if the season starts I obvioulsy do less. my pr is 50.98 I ran it last year indoor, I didn’t run after that beacuse I torned my hamstring in April but i recoverd good from the injury .. I ran my pr with a short to long approach, but I changed coach last year and he had a long to short approach. Since I do the long to short approach I’m getting injured when I do speed drills..

I run the 400m and have the long to short approach, but every time if I want to do some sprinting I pull my hamstring.. Just like Michael johnson had in his first seasons as a senior http://www.dyestatcal.com/ATHLETICS/TRACK/2005/c_hart.pdf Well my question now is how can I prevent to pull my hamstring? I do a lot of long distance and just the one time I want to sprint for some speed work I pull my hamstring every time.