YouthShape.US: A New Anthropometric Resource for U.S. Children and Youth

Objective To characterize the Phase 1 manual anthropometry component of YouthShape.US, document its 57-measure protocol and quality-control procedures, evaluate selected design-relevant differences from legacy and contemporary national reference data, and introduce the publicly accessible YouthShape.US resource. Background Accurate anthropometric data are essential for designing products that safely accommodate children. The most comprehensive U.S. child anthropometry survey was conducted in the 1970s and no longer reflects current populations. Contemporary national sources include few dimensions, while other studies emphasize health outcomes or proprietary sizing systems. Method Phase 1 of YouthShape.US collected laboratory data from 650 children aged 3–17 years. Participants completed a standardized protocol comprising 57 manual anthropometric measurements obtained with calibrated instruments in standing and seated postures, along with body-composition measures. Results Comparisons of 90th percentile values across age showed important differences among datasets. Stature and body weight generally tracked contemporary NHANES estimates more closely than the legacy 1970s U.S. child anthropometry values, although some age- and sex-specific deviations were evident. Body weight and waist circumference were substantially larger than values reported in the 1970s, and buttock–knee length was also larger, indicating changes in seated body dimensions relevant to product and environment design. Conclusion YouthShape.US establishes the first large-scale, detailed, publicly accessible anthropometric resource for U.S. children and adolescents in more than five decades and demonstrates substantial secular changes, particularly in body-mass-related dimensions. Application YouthShape.US provides interactive tools that enable practitioners to explore contemporary body dimensions relevant to product fit, safety, and ergonomic design.