Strength imbalances and prevention of hamstring injury in professional soccer players: a prospective study.

Background: The relationship between muscle injury and strength disorders remains a matter of controversy.

Purpose: Professional soccer players performed a preseason isokinetic testing aimed at determining whether (1) strength variables could be predictors of subsequent hamstring strain and (2) normalization of strength imbalances could reduce the incidence of hamstring injury.

Study Design: Cohort study (prognosis); Level of evidence, 1.