Hamstring stains most commonly occur during running or sprinting activities during the swing phase of the gait cycle just prior to foot strike. In this position there is a high degree of eccentric loading occurring through the hamstring in order to decelerate the leg as it swings forward in preparation for the foot plant. Increased muscle tensile strain also occurs when hip flexion is added as in when bending down to pick up a ball whilst running.
Reduced flexibility makes an athlete more vulnerable to hamstring injuries as greater tensile strain is placed on the hamstrings during the eccentric loading phase.
Previous injury may also predispose to repeated injury due to scar lesions
Key prevention strategies
- Maintain or improve hamstring flexibility with PNF stretching
- Improve hamstring strength especially eccentric loading capacity
Simple test for progress:
- Drag foot of injured leg backwards – assess pain and sore
- “When can I play again”?
- Unfortunately there is a high rate of recurrence.
- A full week of unrestricted top speed training should be performed before re-entering competition
- Anecdotally, in team sports, many recurrences seem to occur because the muscle fatigues more quickly and doesn’t last the distance for an 80-120 min game.
- “When you think you are ready wait a week”