Effects of Walking Exercises on Body Composition, Heart Rate Variability, and Perceptual Responses in Overweight and Obese Adolescents

Objective: To assess the effects of various walking rehabilitation programs on body composition, heart rate variability, aerobic fitness and perceptual responses of overweight and obese young adolescents. Material and methods: 31 young overweight and obese adolescents (12 boys and 19 girls) were randomly assigned to one of 4 groups: a group walking at 70% of maximal aerobic speed (70% MAS G, n=7), a group walking at 50% of maximal aerobic speed (50% MAS group, n=8), a self-selected walking pace group (SSWP group, n=8), and a control group (C, n=8). Anthropometric, metabolic, and perceptual parameters were measured before and after a 2-month rehabilitation program. Results: Decreases in body mass, BMI, and body fat were seen in MAS, 70% MAS, and SSWP groups (p<0.01, p<0.01, and p<0.05 respectively), with associated with increases in the distance performed during the 6MWT (all at p<0.01). 50% MAS and 70% MAS groups showed significant increases in MAS, estimated VO2max, and the calculated maximal fat oxidation (all at p<0.01). In addition, we found a decrease in HR values during the recovery period (p<0.05), associated with significant increases in HF (p<0.05 and p<0.05 respectively) and decreases in LF (p<0.05 and p<0.05 respectively) indices of heart rate variability in 50% MAS and 70% MAS groups. In contrast, the ratio LF/HF decreased only in the 50% MAS group (p<0.05). The 2-month rehabilitation program induced significant decreases of RPE values and Hooper scores in 50% MAS (p<0.05, and p<0.01 respectively) and 70% MAS groups (p<0.05, and p<0.01 respectively). The control group showed no changes in the selected parameters. Conclusions: Rehabilitation programs based on 50% MAS and 70% MAS were more effective strategies to make positive changes on body composition, heart rate variability, aerobic fitness and perceptual responses than the self-selected walking pace, and could be used to ensure an effective intensity of effort in the rehabilitation of overweight and obese adolescents.