Abstract
Since the game of soccer frequently involves one-sided activities such as kicking, tackling and passing, asymmetries in muscle strength between both legs are possible. Low balance ability is generally associated with an increased risk of ligament injuries; the detection of a possible asymmetry in balance is important because a bilateral difference may be a contributing factor to injury.
The monitoring was carried out in fourteen Czech junior elite male soccer players (silver medal from European championship 2011), category U19 (age = 18.6 +- 0.2 years, height = 178.6 +- 5.5 cm, weight = 73.3. +- 6.9 kg). Total travel way (TTW) of centre of pressure as an indicator of postural stability was assessed by force plate Footscan.
Isokinetic strength of knee extensors and flexors on both lower extremities during concentric contraction in 60o.s-1 angular velocity was assessed by dynamometer Cybex Humac Norm (Cybex NORM (R), Humac, CA, USA). We found significant difference in level of TTW between PL and NL in elite junior soccer players (TTWDL = 942.9+-168.9 mm, TTWNL = 1136.5+-251.9 mm, t(13) = -3.73, p{0.01).
Results of study did not reveal significant difference between H:Q ratio of both legs (H:QDL = 59.3+-5.1 mm; H:QNL = 59.1+-8.5 mm; t(13) = 0.10, p}0.05). We found significant correlation between TTWNL and H:QNL (r = -.62, p{.05), in contrast to PL (r = .25, p}.05) where no significant correlation was found.
Relationship between TTWDL and TTWNL was also significant (r = .64, p{.05).