In elite soccer play, hamstring injuries are the most common noncontact injury. As the evidence supporting the use of stretching exercises for the prevention of these injuries is limited, this study examined the relationship between hamstring injuries and the flexibility of the hamstring and ankle.

Over two consecutive soccer seasons, players in all 18 teams in the Qatar Stars league were assessed for injuries. Data collected also included age, playing season, team, leg dominance, playing position, ethnicity, body mass index, as well as ankle and knee range of motion. Hamstring injury was defined as acute pain in the posterior thigh, occurring during training or match play, and resulting in an immediate cessation of participation.

Of the 438 players completing the study, 78 sustained an index hamstring injury. Goalkeepers were significantly less likely to sustain a hamstring injury than were other players. In addition, injured players were, on average, 18 months older than the uninjured. A multivariate regression analysis revealed that age (P＝0.002), player position (P＝0.02), passive knee extension test results (P＝0.008) and dorsiflexion lunge test results (P＝0.02) were significantly related to hamstring injury.

This prospective study of professional soccer players found that modifiable factors related to an increased risk of hamstring injury are decreased knee extension and ankle dorsiflexion passive range of motion.