Factors Associated with Ability and Inter-joint Coordination in Children Performing a Deep Squat

Abstract

Purpose: Deep squatting is an item for musculoskeletal health screening of children in school. The purpose of this study was to explore factors related to ability and inter-joint coordination in this task.

Methods: Forty-seven elementary school children attempted to perform a full squat while keeping both feet flat on the floor. Flexion angles of the hip and knee were recorded during this task. Hip-knee flexion concurrence deviation was assessed as the root-mean square error of hip flexion occurring at the same relative rate as knee flexion. Age, sex, pain or history of injury, sports activities, lifestyle (type of bed), and physical characteristics (degree of obesity, dorsi-flexion angle and strength of ankle, sit-and-reach distance) were recorded as independent variables. Data were subjected to logistic or multiple regression analysis.

Results: Twelve (25.5%) of the children could not squat properly. Significant variables accounting for this were pain or history of injury, degree of obesity, and sit-and-reach distance. Hip-knee flexion concurrence deviation was found to decrease as age increased among the school children.

Conclusion: Ability to squat reflected the condition of physical structural features, while hip and knee coordination during that task improved with development.