DOS 2020

DOS Kongressen 2020 · 187 Hamstring and quadriceps muscle strength in youth to senior elite footballers: a cross-sectional study including 125 players Lasse Ishøi, Kasper Krommes, Mathias Neilsen, Kasper Thornton, Per Holmich, Per Aagaard, Jacob Penalver, Kristian Thorborg Sports Orthopedic Research Center - Copenhagen (SORC-C), Ortopædkirurgisk Afdeling, Hvidovre Hospital; Department of Sports Science and Clinical Biomechanics, SDU Background: Increasing age, high quadriceps strength, and low hamstring strength are associated with hamstring strain injury in football. Purpose / Aim of Study: We aimed to assess the age-related variation in maximal hamstring and quadriceps strength in male elite football players from U-13 to the Senior level. Materials and Methods: We included 125 Elite football players from a Danish professional football club and associated youth academy (1st tier) (U-13, n=19; U-14, n=16; U-15, n=19; U-17, n=24; u-19, n=17; Senior, n=30). Maximal isometric force (MVC) was assessed for the hamstrings at 15o knee joint angle and for the quadriceps at 60o knee joint angle (0o = full extension) using an external-fixated handheld dynamometer. Hamstring:Quadriceps (H:Q) strength ratio as well as hamstring and quadriceps MVC levels were compared across age groups (U-13 to Senior). Findings / Results: Senior players showed 18-26% lower H:Q ratio compared to all younger age groups (p≤0.026). Specific H:Q ratios (mean [95% CI]) were: Senior, 0.45 [0.42;0.48]; U-19, 0.61 [0.55;0.66]; U-17, 0.56 [0.51;0.60]; U-15, 0.59 [0.54;0.64]; U-14, 0.54 [0.50;0.59]; U-13, 0.57 [0.51;0.62]. Hamstring strength increased from U-13 to U-19 with a significant drop from U-19 to the Senior level (p=0.036), whereas quadriceps strength increased lin- early from U-13 to Senior level. Conclusions: Elite senior football players demonstrates lower Hamstring:Quadriceps strength ratio compared to youth players, which is driven by lower hamstring strength at the senior level compared to the U-19 level combined with a higher quadriceps strength. This discrepancy in hamstring and quadriceps strength capacity may place senior level players at increased risk of hamstring strain injuries. 166.