The Effects of Aerobic Exercise Training in Children with Lean and Extremely Obese Biological Mothers

Abstract

The purpose of this study was to compare fat oxidation rates between children of lean biological mothers (CLP) (BMI[less than or equal to]28kg/m[superscript]2) and children of extremely obese biological mothers (COP) (BMI[less than or equal to]40 kg/m[superscript]2); and to determine if aerobic exercise training can improve fat oxidation in both groups in a similar manner. Each participant (n=3 per group) completed two 10 minute submaximal exercise tests at an absolute workload of 15 W and a relative workload of 65% of peak VO[superscript]2. Respiratory exchange ratio was measured during these submaximal workloads to assess differences and changes in fat oxidation. Participants were matched for age, gender, and race and placed into either CLP or COP based on biological mothers BMI. Each child was recruited for 4 weeks, 3 sessions a week for 30-60 minutes. The exercise protocol consisted of aerobic activities such as tennis, tag, and soccer. Each participant was required to maintain a heart rate of > 140 bpm during each training session. This exercise protocol was approved by the East Carolina Institutional Review Board. No significant difference was seen in the initial respiratory exchange ratios (RER) between groups at an absolute submaximal workload (15 W) prior to training or after training (p=0.25). However, both groups showed a decrease in RER indicating increased in fat utilization from pre to post-training (p=0.06). A significant decrease in carbohydrate use was observed during absolute submaximal exercise in both groups (p=0.03). No significant increase was seen fat oxidation during absolute workload (p=0.21) however they did improve slightly. From our results there appeared to be no differences observed between groups, and no changes with exercise at a relative workload. These findings suggest that aerobic exercise training can improve a child's ability to use fat during submaximal exercise and thus decrease the risk of becoming obese in adulthood.