Examination of Hamstring Eccentric Muscle Strength and Limb Asymmetry with Nordbord Device

Aim: The aim of this study was to investigate the hamstring eccentric muscle strength and limb asymmetry in young football players. Materials and Methods: 30 licensed healthy players who competed in the U17 and U19 Elite academy league of Istanbul Başakşehir Football Club participated in the study. Eccentric hamstring strength and limb asymmetry values were assessed while performing nordic hamstring exercise using NordBord device (Vald Performance, Newstead, Australia). Results: Right hamstring eccentric force (r = -0.007, p = 0.971) and mean force (r = -0.195, p = 0.303) have low and non-significant correlations with asymmetry. Left hamstring strength (r = -0.381, p = 0.038) has significant but negative correlations with asymmetry. There is no correlation between torque and asymmetry (p > 0.05). Conclusion: One of the factors that reduces injury in eccentric knee flexor muscle groups is the absence of strength imbalance between the legs. Although there is no consensus on an ideal minimum value for asymmetry, some experts suggest that it should be below 15%. In our study, the asymmetry values of U17 and U19 football players (30 males) were found well below the value (8,55 ± 5,13) recommended by the experts. The low correlation results between right muscle strength and asymmetry in our study indicate that right hamstring muscle strength does not notably effect the asymmetry of the players. In contrast, it was found to have an effect on asymmetry for the left hamstring muscle group strength.