Background and purpose: previous studies showed muscle weakness and muscle imbalance in children can reduce their postural control and increases their risk of falling. The purpose of this study was to investigate the effects of four-week core stability exercises on static and dynamic postural control and isometric strength ratio (agonist / antagonist) of lower extremity muscles in children. Methods: in a semi experimental study twenty children (9 boys, 11 girls) with 3-5 years old volunteered to participate in this study. Subjects performed four-week core stability exercises for three sessions in per week. Postural control and lower limb muscles strength tests performed before and after the four-week core stability exercises. Single leg stance time and Y test were used for measuring static and dynamic postural control respectively. MMT system was used for measuring lower limb muscles strength (hamstring, quadriceps, hip abductors, hip adductors, hip internal and external rotators muscles). Paired sample test was used for comparison pre-test and post-test for per group. The level of significance (alpha) was set at 0.05. Results: findings indicated that four-week core stability exercises have significant effect on static postural control and isometric strength ratio of lower extremity muscles in children (p<0.05) in contrast there is no significant effect in dynamic postural control after four-week core stability exercises (p<0.05). Conclusion: This study highlights that four weeks of core stability exercise can positively effect on static postural control and isometric strength ratio of lower extremity muscles in children but it seems improving of dynamic postural control need to more studies.
