Effect of body mass index on postural balance and muscle strength in children aged 8-10 years

Background:childhood overweight and obesity,which are considered as global epidemic,can be assessed using body mass index (bmi). bmi difference can lead to anatomic changes due to an increased body load. this increase might also affect motor performance,including changes in postural balance and muscle strength. aims and objectives: to explain the influence of bmi on postural balance and lower limb muscle strength and to assess the correlation between those two variables in children aged 8-10 years. material and methods:the sample consisted of 63 children aged 8-10 years,which were divided in 3 groups: bmi-normal,bmi-overweight,and bmi-obese. the postural balance was assessed using single leg balance test on matscan and the center of pressure (cop) area was recorded. isometric muscle strength of hip extensor and knee extensor were measured using a hand-held dynamometer. results: obese children had significantly largercop area than overweight (p = 0.004) and normal weight children (p = 0.000).there were no significant differences in hip extensor muscle strength between obese children with overweight and normal weight children (p=0.527). the absolute knee extensor muscle strength in obese group was significantly higher than the overweight and normal group (p = 0.003). however the relative muscle strength of lower limb for obese children was significantly lower than for normal weight. there was no significant correlation between absolute hip extensor and knee extensor muscles strength with cop area. conclusion: obese children have decreased postural balance and increased absolute knee extensor muscle strength significantly when compared to overweight and normal children. there is no significant correlation between postural balance and muscle strength. © journal of krishna institute of medical sciences university.