Objective: The purpose of this study was to investigate differences in gross motor coordination in healthy-weight, overweight, and obese children of different ages.
Methods: Using a cross-sectional design, data were collected in 954 Flemish primary school children (500 girls, 454 boys) stratified in consecutive age groups (5-7 years, 8-9 years, 10-12 years). Weight status (healthy-weight, overweight, obese) was defined according to the International Obesity Task Force body mass index (BMI) cut-off points for children. Gross motor coordination was assessed by means of the Körperkoordinationstest für Kinder (KTK).
Results: Childhood overweight and particularly obesity were found to result in poorer KTK performances (p < 0.001), with the most apparent effect of BMI on items requiring physical properties next to dynamic body coordination. Expressed as an age-related Motor Quotient (MQ), overall KTK performance was featured by a BMI × AGE interaction (p < 0.01). Healthy-weight children displayed similar MQs across age groups (p = 0.999). Overweight and obese children in the 10-12-year-old group showed significantly poorer motor coordination performance compared with the corresponding 5-7-year-old group (p < 0.01). Less than 20% of the healthy-weight participants was identified as being motor impaired, while that proportion increased to 43.3% and up to 70.8% in children with overweight and obesity, respectively.
Conclusion: Results indicate that BMI-related differences in gross motor coordination were more pronounced as children belonged to an older age group. Although this outcome needs to be confirmed in future longitudinal research, it emphasizes the need of an early focus on motor skill improvement to encourage overweight and obese children to be physically active.