Body Fat and Muscle Mass in Association with Foot Structure in Adolescents: A Cross-Sectional Study

Prior studies have investigated associations between body mass index (BMI) and foot structure; however, these studies are limited only to the evaluation of the longitudinal arch of the foot and do not evaluate associations with body composition. Therefore, this study examined associations between body fat percentage (BFP) and muscle mass percentage with foot structure in adolescents. This study was conducted with 158 healthy subjects aged from 11 to 13 years. Body fat percentage and muscle mass percentage were estimated using bioelectrical impedance analysis. A podoscope was used to calculate Clarke's angle (CL), the Wejsflog index (WI), hallux valgus angle (ALPHA), and the angle of the varus deformity of the fifth toe (BETA). Lower values of CL were found in participants with excessive BFP (p = 0.021). No differences were observed in the values of the Wejsflog, ALFA or BETA indices between normal and excessive BFP groups. Participants with the lowest muscle mass percentage were significantly more likely to have lower values of CL and WI (p = 0.014 and p < 0.001, respectively). Excess BFP appeared to have a significant effect on the longitudinal arch and low muscle mass percentage on the longitudinal and transverse arches of the foot in adolescents. There was no association between fat and muscle content with positions of the big and fifth toes.