(12) Three-dimensional body scan measurements identify performance potential during military load carriage

Defined relationships between anthropometrics and physical performance are important for setting appropriate military physical fitness standards for warfighters of varying sizes but are historically difficult to analyze comprehensively due to technological limitations. Three-dimensional scanner (3DS) technologies are a novel analytical tool for rapid collection of hundreds of body measurements that may identify performance potential in militarily-relevant tasks.

Purpose: Identify 3DS measurements indicative of optimal performance of individuals during heavy military load carriage.

Methods: Three-dimensional body surface scans were collected from 39 male US Army Soldiers and civilians (age, 24 ± 6 y; height, 177 ± 7 cm; mass, 82 ± 14 kg) using a multi-camera infrared booth 3DS (Size Stream LLC; Cary, NC). Participants performed incremental walking tests to determine the highest sustainable pace with a respiratory exchange ratio ≤ 1.0 when carrying a load equal to 44% body mass. Key performance indicators were identified from 174 different 3DS measurements using an iterative, nested multiple regression modeling approach. Goodness-of-fit was evaluated based on the Akaike Information Criterion (AIC) and multiple coefficients of determination (R²).

Results: The highest sustainable walking pace for carrying a 44% body mass load was 6.2 ± 0.5 km/h. The best fitting model (AIC = 33.6, R² = 0.67) included six 3DS measurements: two circumferences (head, knee), three arcs (posterior chest, posterior hip, lower posterior chest), and one length (abdomen rise).

Conclusions: The considerable variance explained by the six identified 3DS measurements is clear evidence that 3DS technologies provide valuable information for identifying performance potential during heavy military load carriage. Leveraging 3DS technologies for determining performance limits and potential of individual warfighters during other mission-essential tasks is critically important for military communities. PRACTICAL APPLICATIONS: Tactical strength and conditioning coaches can use information from 3D body scans for individualized training periodization.

Acknowledgements: The views expressed in this abstract are those of the authors and do not reflect the official policy of the U.S. Government, Department of Energy, Department of the Army, or Department of Defense.