Effect Of8-week Lower Extremity Resistance Exercise On Muscle Strength And Gait In Obese Children

Objective:The purpose of the study was to determine the effect of an8-week lower limbsresistance training intervention on muscle strength and gait of obese children, toanalysis whether muscle strength could improve the impact of excess body weight ongait in obese children. Moreover the study can provide the more information aboutresistance exercise in obese children which is few documented.Method:34obese children aged10-11years old were randomly allocated to an resistancegroup (n=17)（RG） or a control (n=17) group （CG）. Subjects in the resistancegroup participated in8-weeks lower extremity resistance training conducted by elasticband, the control group does not participate in resistance training. Muscle strength,gait kinematics and kinetics, and energy expenditure during walking outcomes wereassessed by CON-TREX, K4b2, VICON, respectively. A paired T-tests was used tocompare differences between before and after intervention. A independent sample ttest was used to compare difference of change value between RG and CG. Finally weuse “Statistical Package for Social Science for Windows19.0” analyzed all the data.Results:1. There were no significant for height, weight, BMI, waist, hip and waist hip ratiobetween RG and CG children, the increased trend were showed in weight andBMI.2. Except the knee extensor, all muscle strength had improved in RG. The an ankleplantarflexion knee absolute strength increased by15.5%, the absolute strengthincreased by23.2%, knees relative strength increased by15.3%, ankledorsiflexion and toe down relative strength increased by14.0%and12.2%. theknee absolute strength and relative strength of control group had decreased by4%and9%.3. There were significant time-by-group interactions for muscle strength, walkingspeed, stride time, hip joint peak moment in RG.4. There were differences in total mechanical energy and mechanical efficiency. Thetrend were showed in total energy cost, net energy.Conclusion:1. In the8-week resistance intervention, muscle strengthening in lower extremitiesimproved obese children’s lower muscle strength.2. After improved strength, the walking velocity, the stride time, total mechanicalenergy and mechanical efficiency in RG. Recommended emphasizes theresistance exercise of lower limbs in the obese children fitness guidance.