Flat feet occurrence among young school-age children and its association with body mass index values

A sedentary lifestyle, characterised by a lack of physical activity, negatively influences Body Mass Index (BMI). BMI may be related to the prevalence of flat feet. This study aims to observe the occurrence of flat feet in young children and determine its association with BMI. Additionally, it aims to analyse foot loading in the forefoot, midfoot and rearfoot. Dynamographic records of children (N = 142; age = 10.3 ± 0.21 years) were collected during walking, and foot-type evaluations were conducted using a force plate. A normal foot type was observed in 44% of children (BMI 16.0 ± 2.3 kg/m²). Flat feet were observed in 54% of children (BMI 18.4 ± 4.3 kg/m²). A high foot arch was observed in only 2% of children (BMI 16.0 ± 1.3 kg/m²). Children with flat feet had higher BMI values than those with normal feet. The contact time and maximal vertical force in the forefoot and rearfoot were similar in children with normal and flat feet. Significantly higher pressure values were observed in the midfoot zone of children with flat feet. Regression analysis results showed that in children with flat feet, there is a decrease in forefoot loading and an increase in midfoot loading with increasing BMI. This trend was not observed in children with normal feet. We recommend incorporating exercise interventions at this age to prevent pain and promote willingness to engage in physical activity. Higher BMI values indicate an increased risk for the prevalence of flat feet.