Well, the reason why I feel sprinters get hamstring injury’s is due to the intake of creatine and not enough weight room work for the posterior chain muscles.
Seriously, if you are a sprinter you need to put aside the arm curls and get with the glute ham raise, the back extensions, the reverse hypers, the dead lifts, the rack pulls; HARD!
The only time I suffered from a hamstring injury was when I was under a coach who did not pay much attention to the weights and on the track we would run at an 70-80% effort at every practice.