Women In Combat: An Opportunity to Increase Lethality At All Levels

By Dr. Krista Austin, O2X Sleep Specialist

The press has been abundant with commentary on Secretary Hegseth’s new study, fueled by concerns over women’s combat capabilities and understanding the impact of new physical fitness standards for combat occupations.¹ Both actions open doors, and if approached correctly, the study can identify opportunities for targeted investment in our combat units to enhance lethality. 

In 2015, each service branch released single gender-neutral fitness standards as the initial screen for a combat occupation.^2-3 None were developed for once the occupation was obtained. From the point of screening, each branch differed in the approach to developing gender-neutral minimum standards for occupational skills. In 2022, the Army would deviate from its gender-neutral standards screen on the Army Combat Fitness Test (ACFT) and implement gender and age-normed standards.^4-5 

The Congressional mandate required standards be gender neutral and no greater than the occupational demand.^2-3 Gender-neutral means one standard for everyone. Demonstrating a standard is no greater than the occupational demand entailed accounting for relevance in combat. While occupational tasks are more clearly defined, physical fitness tests are not as simple, given their lack of a directly proportional relationship to minimum occupational standards.

After 10 years of integration, the new study will address concerns that have continued to fuel questions around the integration of women and the relationship of physical fitness to occupational performance.  Published findings on previously closed occupations highlight gaps in knowledge about operational success:

• 2004 Special Operations Combat Medic (SOCM) course graduates, first female.⁶
  
  • Reduced prevalence of female graduates
  • Greater prevalence of critiques for upper body strength in women. 
• 2015 Marine Corps Ground Combat Element Integrated Task Force (GCEITF) identified the following in mixed gender units:^7-8
  
  • Women had greater rates of musculoskeletal injury (males: 18.8% vs women: 40.5%). Fitness mitigated differences in injury rate.
  • All male units outperform mixed gender units in 69% of ground combat tasks; predominantly infantry tasks.
  • Artillery, combat engineers, tanks, and amphibious assault occupations showed minimal performance impact
  • Infantry and crew-served weapons occupations showed reduced performance. Body weight was related to performance. 
• 2022 Women passing the Ranger Course (RC) and Marine Corps Infantry Officer Course (IOC)⁹ 
  
  • Lower absolute VO_2max scores compared to male Special Forces (SF) 

Research by the National Basketball Association has highlighted the lack of relationship between physical fitness and performance when there are high stakes, uncertainty, and a need to account for team effectiveness.¹⁰ Similarly, this must be considered when looking at combat effectiveness. To understand how physical fitness and teamwork impact lethality, we must consider the following:

• work capacity, 
• minimum standards 
• identifying an individual range to maximize team contribution. 

‍

Work Capacity

Work capacity is necessary for any physical effort to be sustained and must be comparable among team members. Comparisons of work capacity can be examined from an individual’s run time (aerobic capacity) and strength levels. Absolute values allow for equivocating between individuals regardless of gender, age or body weight.

Cardiovascular Fitness

The Marine Corps GCEITF highlighted aerobic capacity (VO_2max) as critical to success in combat occupations. Elite female athletes demonstrate the upper levels women can reach, with sports such as rowing and cross-country skiing obtaining aerobic capacities of 5.0-5.5 L/min VO_2max. ¹¹ Female graduates of RC and IOC provide an average of 3.3 L/min and a range of 2.2-3.86 L/min.⁹ In comparison, estimates of aerobic capacity in the Army’s Special Forces (SF) provide a range of 3.3 L/min to 5.7 L/min.⁹ The overlap in VO_2max ranges demonstrates that women can obtain the same level of absolute aerobic capacity for combat occupations.

Strength

Young adult powerlifters (18-35 years of age) have demonstrated the following strength capabilities per pound of body weight for gender: bench press: males 1.95, females 1.35; deadlift: males 3.25, females 2.66; squat: males 2.83, females 2.26.¹² Recommendations for preparation to SF Assessment and Selection (SFAS) suggest a deadlift of 310 pounds.¹³ With average male candidates for SFAS weighing 180-190lbs and women in RC and IOC weighing 114-176lbs, this is 1.6-1.7lbs and 1.8-2.7lbs per pound of body weight, respectively.^9,14 These findings highlight the need to consider absolute strength relative to body weight.

Body Weight

Body weight is one of the main factors identified by the Marine Corps GCEITF as critical to successful integration.^7-8 This is not surprising, given it supports absolute VO_2max and strength levels. In addition, performing heavy load carriage is recommended not to exceed 45% of body weight¹⁵ and special operations high-risk components have a weight requirement for these reasons. Thus, optimizing body weight is crucial to success.

Teamwork

In combat elements, the role of a team is consistently emphasized.  One of the findings highlighted by the Marine Corps GCEITF was that minimum standards could not answer how best to address disparities when mission performance required teams to perform occupational skills at a level greater than the minimal standard. Regardless of the minimum standard, you must be able to go with your team. 

In training a Special Forces ODA, when a mission required an increased level of work capacity for lethality purposes, the team sergeant directed that everyone was expected to achieve it. Training from performance analysis showed a level of demand that could not be evaluated by the minimal standard or the ACFT. In this instance, male Special Forces without these capabilities were not considered for the team. 

Determining how best to address teamwork and the need for performing above the minimal standard is challenging. Solutions may include allocating team members based on physical capabilities relative to the minimum standard or mission requirements. The recent implementation of a Navy Combat Fitness Test for all team members working within the Naval Special Warfare Command highlights the latter, in which requirements are relative to mission purpose.¹⁶ 

Maximizing Versatility

In pursuit of work capacity and teamwork, each individual can develop a range within which they can optimally operate and maximize versatility for their team. How does this apply to your occupation? Here is a model from working on a project related to women in combat:

1. Evaluated known aerobic capacity, strength levels and body weight
   
   1. Aerobic capacity: at least 3.5 L/min
   2. Strength: Up to 2.0lbs per lb of body weight
   3. Body weight: Range of 155-175lbs
2. Evaluated body weight in relation to height (66”) and body mass index.
   
   1. For infantry heavy load carriage and elite military operators, BMI 25-28
3. Progressively evaluate run times versus heavy load carriage.
   
   1. Capable of absolute strength for elite military operators, moderate run capabilities, ruck running, and load carriage at 175lbs.
   2. Best economy for running/ruck running with SFAS strength levels at 160-165lbs.
   3. Ability to decrease body weight easily from 160-165lbs to 150-155lbs.
      
      1. Allows for elite mission-critical skills requiring minimum body weights
      2. On a low-carbohydrate diet, weight could be reduced further.
      3. Versatility in body weight brings additional unconventional warfare capabilities for teams requiring a female to work in varied roles. 

The above is a suggested approach for refining operational capability and maximizing an individual’s characteristics for variations in the mission set. When lethality is the goal, the study should identify parameters that can optimize teamwork and the best use of an individual’s capabilities. 

About O2X Sleep Specialist Krista Austin:

Krista is a physiologist with +15 years of experience working with tactical populations and +25 years in elite sport. Her first work in tactical human performance was in supporting increased lethality of a SEAL team by addressing challenges of combat at altitude. She supported the Marine Corps gender neutral standards development, embedded with Marine Recon to prepare for projects on women in combat, including addressing concerns surrounding the integration of women. Her work with Special Forces highlights that operational capability, rather than gender, is what matters.

References:

1. Farina, E. K., Stein, J. A., Thompson, L. A., Knapik, J. J., Pasiakos, S. M., McClung, J. P., & Lieberman, H. R. (2025). Longitudinal changes in psychological, physiological, and nutritional measures and predictors of success in Special Forces training. Physiology & Behavior, 291, 114790. https://doi.org/10.1016/j.physbeh.2024.114790
2. Fiset, J. (2024). Talent selection under uncertainty: Exploring cognitive biases through the lens of a professional basketball entry draft. Management Teaching Review, 0(0). https://doi.org/10.1177/23792981241260634
3. Givens, M. L., & Eklund, K. (2019). Females engaged in elite training previously only open to males: Exploring the variables of successful outcomes. Military Medicine, 184(Suppl. 1), 438–442. https://doi.org/10.1093/milmed/usy291
4. Hardison, C. M., Hosek, S. D., & Bird, C. E. (2018). Establishing gender-neutral physical standards for ground combat occupations: Volume 1. A review of best practice methods. RAND Corporation.
5. Hardison, C. M., Hosek, S. D., & Saavedra, A. R. (2018). Establishing gender-neutral physical standards for ground combat occupations: Volume 2. A review of the military services’ methods. RAND Corporation.
6. McClung, H. L., Lieberman, H. R., Thompson, L. A., Farina, E. K., & Beckner, M. E. (2025). One force: Limited sex differences in retrospective assessment of physiological and psychological attributes of elite warfighters. Journal of Applied Physiology, 139(1), 231–238. https://doi.org/10.1152/japplphysiol.00197.2025
7. van den Hoek, D. J., Beaumont, P. L., van den Hoek, A. K., Owen, P. J., Garrett, J. M., Buhmann, R., & Latella, C. (2024). Normative data for the squat, bench press and deadlift exercises in powerlifting: Data from 809,986 competition entries. Journal of Science and Medicine in Sport, 27(10), 734–742. https://doi.org/10.1016/j.jsams.2024.07.005
8. van der Zwaard, S., Brocherie, F., & Jaspers, R. T. (2021). Under the hood: Skeletal muscle determinants of endurance performance. Frontiers in Sports and Active Living, 3, 719434. https://doi.org/10.3389/fspor.2021.719434
9. Center for Military Readiness. (2015). U.S. Marine Corps research findings: Where is the case for co-ed combat? https://www.cmrlink.org/issues/full/army-scraps-genderneutral-standards-pushed-by-discredited-social-engineers
10. Marine Corps Operational Test and Evaluation Activity. (n.d.). Ground Combat Element Integrated Task Force experimental assessment report.
11. U.S. Army Special Operations Command. (2025). Special Forces Assessment and Selection (SFAS) preparation handbook. https://www.goarmysof.army.mil/Portals/100/Documents/SFAS%20Preparation%20Handbook25June25.pdf
12. U.S. Army. (2015). Military Review article. https://www.armyupress.army.mil/Portals/7/military-review/Archives/English/MilitaryReview_20150430_art009.pdf
13.  National Public Radio. (n.d.). Pentagon to review women in ground combat positions. NPR.
14.  Szivak, T. (n.d.). Resistance exercise considerations for load carriage. NSCA Tactical Strength and Conditioning (TSAC) Report.
15.  U.S. Navy. (n.d.). Combat Fitness Test: Guide 5B.

About O2X Sleep Specialist Dr. Krista Austin:

Dr. Krista Austin is a Human Performance Specialist with more than 25 years of experience advancing resilience, recovery, and readiness across elite sport, tactical, and high-performance environments. She combines scientific rigor with practical application to help individuals and organizations perform at their best under pressure. Krista earned her Ph.D. in Movement Science from Florida State University and is a Certified Strength and Conditioning Specialist (CSCS) through the National Strength and Conditioning Association. Her diverse career spans leadership and consulting roles with the U.S. Olympic & Paralympic Committee, English Institute of Sport, and multiple U.S. national governing bodies, where she served as High Performance Director. She has also consulted for professional sports organizations, helping teams integrate evidence-based performance, nutrition, and recovery strategies to optimize athlete health and success. In the tactical domain, Krista has supported military research organizations and elite military units, developing performance solutions to enhance readiness and resilience in high-stress environments. Her work bridges research and operational practice, focusing on the human factors that drive sustained performance and recovery. At O2X, Krista specializes in the science of winning with a focus on sleep to optimize resilience helping tactical professionals understand how sleep impacts physical readiness, decision-making, and long-term health. She provides education that empowers individuals to improve sleep quality, enhance resilience, and maintain mission effectiveness in demanding environments.