Physical Activity, Body Composition, and Ultrasonographic Characteristics of the Anterior Abdominal Wall in School-Aged Children

Introduction: Physical activity is an important determinant of healthy growth and body composition during childhood. However, its association with ultrasonographic characteristics of the anterior abdominal wall remains poorly understood. This study aimed to evaluate the relationship between physical activity level, anthropometric parameters, body composition, and ultrasonographic characteristics of the anterior abdominal wall in school-aged children.

Methods: This cross-sectional study included 52 children aged 8–12 years (mean age: 9.0 ± 1.1 years), including 20 girls (38.5%). Physical activity was assessed using the Physical Activity Questionnaire for Older Children (PAQ-C). Participants were classified into lower-activity (PAQ-C < 3) and higher-activity (PAQ-C ≥ 3) groups. Anthropometric assessment included body mass index (BMI), BMI percentile, and waist-to-hip ratio (WHR). Body composition was evaluated using a bioelectrical impedance analyzer (Tanita DC-430MA, Tanita Corporation, Tokyo, Japan). Ultrasonographic assessment of the anterior abdominal wall included measurement of the inter-rectus distance.

Results: Children with higher physical activity levels had significantly lower BMI (16.88±2.36 vs. 18.56±2.76 kg/m²; p=0.014), BMI percentile (43.04±27.20 vs. 62.17±25.04; p=0.007), body fat percentage (17.63±5.09 vs. 20.86±6.71%; p=0.037), and fat mass (5.91±2.98 vs. 8.73±4.91 kg; p=0.011) compared with less active children. A significant difference in WHR was also observed between groups (0.89±0.04 vs. 0.86±0.04; p=0.028). No significant differences were found in fat-free mass or ultrasonographic parameters of the anterior abdominal wall.

Conclusions: Higher physical activity levels were associated with a more favorable body composition profile and lower adiposity in school-aged children. No association was observed between physical activity level and ultrasonographic characteristics of the anterior abdominal wall muscles.