Can a clinical test of hamstring strength identify football players at risk of hamstring strain?

PURPOSE: To demonstrate the potential for a simple clinical test of hamstring muscle strength to identify susceptibility to muscle strain injury.
METHODS: A single-case design was used; specifically, an elite-level male Australian Rules football player performed bilateral isometric maximum voluntary contractions of the hamstring muscles on a weekly basis for a period of 5 weeks preceding a right hamstring muscle strain injury.
RESULTS: Minimal asymmetry (no greater than ±1.2% difference) was evident in the hamstring isometric maximum voluntary contractions during the first 4 weeks, but 5 days prior to injury, the right hamstring isometric maximum voluntary contraction was reduced by 10.9% compared to the left.
CONCLUSION: Measuring asymmetry in isometric maximum voluntary contractions of the hamstring muscles may be a useful clinical test to identify susceptibility to muscle strain injury.