Relation between body mass index percentile and muscle strength and endurance
Background: Muscle strength and endurance in children are very important to develop
physical activities and cardiorespiratory functions, so factors that might affect their development must be studied; thus the aim of this study is to identify if there is a relation between body mass index percentile and muscle strength and endurance time in healthy normal and obese children.
Subjects and methods: A group of 75 healthy children without orthopedic, perceptual or cognitive problems were selected from Awlady Association in Maadi, Cairo, their ages ranged from 10 to 13 years old from both sexes. They were divided into three groups according to their body mass index percentile where group (a) is equal to or more than 5% percentile yet less than 85% percentile, group (b) is equal to or more than 85% percentile however under 95% percentile, while group (c) is equal to or more than the 95%th percentile. Two assessments had been carried out with respect to the peak torque for triceps muscle and quadriceps muscle, they were surveyed by Biodex isokinetic dynamometer at an angular velocity of 60/s in concentric contraction mode while abdominal muscles were evaluated by manual muscle testing. A stop watch was utilized to calculate the length of time to fatigue to evaluate endurance time.
The results: A significant distinction in muscle strength and endurance time among the obese, overweight groups comparing to the normal weight groups was identified. Additionally there was a positive correlation between muscle strength and body mass index percentile while muscle endurance time had a negative correlation with it.
Conclusion: The study shows that the BMI of children had a positive correlation with the muscle strength of quadriceps, triceps, and abdominal muscles while a negative correlation with the endurance time of these muscles.