Hamstring injury prevention: the strength assessment in young soccer players

Aim: The hamstring strength training in youth soccer is relevant both for muscle injury prevention and for sprint performance increase. This study aim to assessment hamstring eccentric strength in young soccer players to know any lower limb strength asymmetries Methods: The sample is composed of male young soccer players Under 17 (n=14, 16,6±0,5 years, 175,8±7,1cm and 70,9±9,1 kg). To assess the hamstring eccentric strength and the lower limb eccentric strength asymmetry have been used a specific dynamometer (NordBord Hamstring Testing System, Vald Performance, Australia) with software. Every young soccer player performed a single repetition of the Nordic hamstring exercise with constraint to the Nord Bord; after about 10 minutes, instead, they performed 5 repetitions of the same exercise, without interruption. All values were acquired using NordBord software: for both assessments, were detected the eccentric strength and the lower limbs strength asymmetry. Results: The evaluation of the hamstring eccentric strength does not show substantial and statistically significant differences in the single test with reference to the peak parameter. In the comparison between the average eccentric strength expressed in the 5 repetitions there is a statistically significant difference between the values expressed by the two limbs (p<0-05), and an increase in the value asymmetry is observed (15,8±5,4%). Conclusion: This difference between the two tests leads us to think that the fatigue potential effect on the hamstring muscles deriving from the number of repetitions requested, can accentuate and highlight to a greater extent the differences between the hamstrings of the two lower limbs in the young player.