Energy Cost of Walking in Adolescents With Obesity: Impact of the Degree of Obesity.

PURPOSE: It is well described that adolescents with obesity show a higher cost of walking (Cw) compared with their lean counterparts, but it remains unknown how the degree of obesity and adiposity impact this Cw in this population. The present study, a secondary analysis of the EBOY cohort (Energy Balance and Obesity in Youth), explores the influence of the degree of obesity and adiposity on the Cw in adolescents with obesity.

METHOD: The Cw was assessed using indirect calorimetry, and body composition was measured by dual-energy X-ray absorptiometry. Participants were divided into tertiles based on their anthropometrics and body composition outcomes.

RESULTS

The present study shows a tertile effect for body weight, z-score of body mass index, fat-free mass, and fat mass (FM; in kilograms) on gross and net absolute Cw (P < .001), while there was only a FM (in percenatage) tertile effect on net absolute Cw (P = .045).

CONCLUSION

Cw in weight stable adolescents suffering from obesity seems to be mainly under the influence of the mechanical load imposed by the increase of body weight, z-score of body mass index, fat-free mass, and FM in kilograms, while the effects of the percentage of FM appears to be less clear and remains to be further explored.