The Metabolic “Pink Taxing” of Fitness Standards for Female Service Members

by Allison Brager, PhD, and Valerie Starratt, PhD
TSAC Report May 2024
Vol 72, Issue 1


This article will explore the concept of “pink taxing,” whereby females must expend more metabolic energy compared to their male counterparts to achieve the same scores in standard military fitness tests.

Author Note: We have no conflicts of interest to disclose.

The opinions herein represent those of the author and do not reflect official viewpoints of the federal government, Department of Defense, and Department of the Army.

An independent review of the original implementation of the United States Army Combat Fitness Test (ACFT)— using data collected from 2019 through September 10, 2021—found that female soldiers failed the test at substantially greater rates than male soldiers, with failure rates of 48% for female enlisted soldiers compared to 8% for male enlisted soldiers and 28% for female officers compared to 4% for male officers (9). Again in 2023, a study showed results that females struggled to pass the ACFT at higher rates than males (21). This result has been central to a larger ongoing debate, primarily within the United States Congress, about gender-neutral and job-specific standards for military readiness. One reason for the sex difference in success rates and the associated debate about readiness standards is inherent sex differences in basic biology and physiological functioning, which effectively rendered the fitness requirements to pass the ACFT more difficult for female soldiers. The following evaluation of fitness standards in terms of sex-specific norms and biological constraints will present a discussion that, compared to their male counterparts, female soldiers must expend more metabolic energy and function substantially closer to peak possible performance to meet or exceed minimum fitness requirements. Potentially, this means that a female soldiers must reach greater relative levels of achievement to earn the same ACFT score as male counterparts. This article will explore this discussion and present the logic that leads to this conclusion, which is rooted in an appropriate understanding of core sex differences in biology. 

This article originally appeared in TSAC Report, the NSCA’s quarterly, online-only publication geared toward the training of tactical athletes, operators, and facilitators. It provides research-based articles, performance drills, and conditioning techniques for operational, tactical athletes. The TSAC Report is only available for NSCA Members. Read more articles from TSAC Report 



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Allison Brager

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Major Allison Brager is the Deputy Chief Science Officer of the United States Army John F. Kennedy Special Warfare Center and School. She has a Bachel ...

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