Abstrakt
The purpose was to compare knee extensors and flexors' strength in sedentary children and detect its differences with respect to gender and lower limb dominancy. It was hypothesized that the non-preferred leg would have lower knee extensors and flexors' strength and there will be a higher incidence of bilateral and unilateral strength deficit.
The group of untrained children (boys: n = 20, age = 14.5+-0.2 years, height =171.1+-5.3cm, weight = 60.4+-20.3 cm, girls: n = 18, age = 11.6+-0.4 years, height =163.5+-5.0 cm, weight = 55.2+-8.9 cm) was tested on the Cybex isokinetic dynamometer at 60 o.s-1 for the dominant (DL) and non-dominant leg (NL) in concentric contraction. Univariate ANOVA (2x2) with two between subject effects (gender (G), laterality (L)) was used for evaluation of peak torque (PT) differences between the factors for extensors or flexors.
Strength of knee extensors (PTE) and flexors (PTF) was significantly different depending on gender (PTE: F1,76 = 23.92, p.05, ηp 2= .01) and PTF (F1,76 = 0.48, p>.05, ηp 2 = .01). The interaction effect between velocity and gender was insignificant (p>.05).
Bilateral strength deficit between the limbs (Q:Q) was 7.27 % in boys and 1.78 % in girls. The PTE and PTFwas significantly different depending on G in 15-year-old participants.
Limb dominancy did not significantly influence isokinetic strength of knee extensors and flexors. The bilateral strength deficit between the limbs was < 10%in both groups.The unilateral ratio (H:Q) ratio was higher in boys than in girls.
Early identification of muscle imbalances and their compensation using verified intervention procedures should be a part of movement intervention at schools, sports clubs and free time activities in youth age with the aim of early elimination of the detected maladaptive effects.