Abstract
Personal armors were initially designed to fit against the male torso, as men previously filled roles requiring them, thus not made to accommodate the female anatomy. As a result, armor worn by female warfighters tends to have non-form fit in the waist, armpit, bust, and collarbone areas, causing reduced coverage. Shifting, riding up, air gaps, breathing difficulty, and physical discomfort have also been observed. Although this has been documented, the impact on the armor’s protective capabilities has not been well studied. To address this, this study compared the protective capabilities of unisex armor for male and female warfighters from shock threats. Instrumented manikins were exposed to free-field blasts to assess pressure exposure in as-worn conditions. Directionality effects were considered in this study, using five directions from the shock source. It was found that the most harmful exposure to both warfighters occurred during a head-on interaction, with average impulse values 9.7%-72.6% higher than other orientations and peak pressures being 111.0 and 107.9 kPa, respectively. Moreover, a female body shape altered armor fit to increase impulses by up to 78.6%, relative to no armor being worn. This result was not observed for the male warfighter, though peak pressures were reduced for both.
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The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
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Acknowledgements
The authors of this paper want to acknowledge members of the Missouri University of Science and Technology Energetics Research Team for their assistance in completing the necessary experimentation. Funding for this work was through Army Research Laboratory (ARL) Award #W911NF-24-2-0093 as well as internal funds of Dr. Johnson at Missouri S&T.
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Melissa Sutter led the study design and experimental process and wrote the initial draft of the manuscript. Dr. Catherine Johnson assisted with the interpretation of the result, manuscript revision, and provided internal funding for the experiments performed. All authors reviewed and approved the final manuscript.
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Funding for this work was through Army Research Laboratory (ARL) Award #W911NF-24-2-0093 as well as internal funds of Dr. Johnson at Missouri S&T.
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Sutter, M., Johnson, C. Sex-based effects of shock energy exposure in warfighters. Sci Rep (2026). https://doi.org/10.1038/s41598-026-47358-0
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DOI: https://doi.org/10.1038/s41598-026-47358-0
