Clinical & Experimental Cardiology
Open Access

Abstract

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

Ali Hamila, Mohamed Younes, François Cottin, Yasmine Ben Amor, Roy Shephard, Zouheir Tabka and Ezedine Bouhlel

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.