Abstrakt
The aim of the study was to determine the profile of muscular strength and strength asymmetries of national male soccer players (n = 25, age = 15.6 +- 0.2 years, body height = 177.4 +- 6.8 cm, body mass = 67.0 +- 7.7 kg). The muscular strength of the lower limbs was assessed using a Cybex Humac Norm isokinetic dynamometer (Cybex NORM (R), Humac, CA, USA).
The maximum peak muscle torque of the knee extensors (PTE) and flexors (PTF) of the dominant (D) and non-dominant leg (N) during concentric contraction were measured at three angular velocities of movement (60, 120, 180, 240 and 300 o/s). The muscular strength of knee extensors and flexors were significantly reduced with increasing movement velocity in both extremities (p<0.05).
Significant differences were found between muscle strength of extensors at 240 and 300 o/s, and flexors at the lowest velocity (p<0.05). Hamstring to quadriceps ratio (H:Q) between legs at 240 o/s was significantly different (p<0.05).
Our study indicated that almost 60 % of young male players have at least one strength asymmetry (bilateral knee flexor or quadriceps) regardless of their limb's preferences. Screening examination of muscle strength asymmetries is a useful tool for prevention of muscle injuries in young soccer players.
The strength asymmetries represent a potential risk of a player's injury; therefore the detected asymmetries should be systematically monitored and compensated using specific exercises.