The Effects Of 4-week Aerobic Exercise-induced Fat Loss On Obese Female Adolescents With Different Waist-to-height Ratio

PURPOSE: Diet-and exercise-induced weight loss intervention has been frequently reported as an effective method for obese people attempting weight loss.It is also noted that the effectiveness varies among individuals after the same intervention.Previous studies suggested the effectiveness of a weight loss intervention for obese individuals,however the independent effects of obese individuals' body shape on the reduction of obesity and related comorbid conditions following an intervention are still unclear,especially for diet-and exercise-induced weight loss interventions.The purpose of this study is to determine differences in the rate and effect of exercise-induced weight loss intervention on obese female adolescents with two different body shapes(central obesity and peripheral obesity).METHODS: 60 obese female adolescents were recruited from a 4-week weigh loss summer camp.All participants received a full medical examination and an interview to determine their suitability and willingness to adhere to the intervention before they were enrolled.The intensity of the exercise was light to moderate and the daily calorie intake was provided as 3 meals and 1 snack each day by registered dietitians.Blood samples were collected pre-and post-intervention for evaluation of serum lipids,fasting insulin and glucose levels.Anthropometric parameters,body composition,blood pressure and cardiovascular fitness were also measured.Based on their Waist-to-height ratio(WHt R),the participants were divided into central obesity group(WHt R?0.5,n=30)and peripheral obesity group(WHt R<0.5,n=30)for analysis.RESULTS: Participants lost about 8.1% of their body weight(p< 0.01),which was attributable to a 20.9% reduction in fat mass(P< 0.01).In both central obesity group and peripheral obesity group,Waist circumference(WC)and hip circumference(HC)decreased after weight loss.Participants in the central obesity group had a higher rate of weight loss and fat loss and more reduction in WC,WHR,WHt R than participants in the peripheral obesity group.A further DEXA data showed that those participants in the central obesity group lost more Android body fat than Gynoid body fat.Decreases in total-cholesterol,LDL cholesterol,triglycerides,fasting insulin,and HDL cholesterol to LDL cholesterol ratio(all P < 0.05)were noted for both group,and no group difference was found.CONCLUSIONS: Obese female adolescents with central fat distribution tend to lose more weight than those obese female adolescents who were classified as peripheral obesity after a diet-and exercise-induced(light to moderate exercises)weight loss intervention.However,the improvement of insulin resistance and lipid metabolism of two groups were not significant.Exercise-induced weight loss is associated with a preferential reduction in abdominal fat.WHt R can be considered as an factor when developing an exercise weight loss program.