1
|
Beckner ME, Stein JA, Lee MR, Knapik JJ, Farina EK, Smith TJ, Van Dam D, Barringer ND, Larsen M, Lieberman HR. Sex differences in mood, hormone and immune response to combatives training in West Point Cadets. Psychoneuroendocrinology 2024; 159:106656. [PMID: 37918137 DOI: 10.1016/j.psyneuen.2023.106656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/22/2023] [Accepted: 10/22/2023] [Indexed: 11/04/2023]
Abstract
Hand-to-hand combat training, known as combatives, instructs Soldiers in close-quarters combat techniques and how to cope with stress, understand controlled physical aggression, and develop self-confidence when engaged in such activities. Limited research in combat sports suggests men and women may respond to combatives stress differently. Given the increasing integration of women into close combat roles in the military, investigation of sex differences in the physiological and psychological response to combatives among military-trained personnel is warranted. PURPOSE This study was designed to identify sex differences in stress and gonadal hormones, mucosal immunity, and mood states in a military combatives training course. METHODS U.S. Military Academy Cadets (men = 144, women = 37) enrolled in a 2-month Combat Applications Course at West Point completed the Profile of Mood States and Competitive State Anxiety Inventory-2 and provided salivary samples at baseline prior to the course, and immediately prior to their midterm and final combat matches. Combat matches were gender- and weight-matched. Additional salivary samples were collected immediately following the first midterm and final matches. Salivary cortisol, testosterone, secretory immunoglobulin A (SIgA) and estradiol (women only) were measured via immunoassay. Men and women were compared over time with linear mixed effects models. RESULTS In both men and women, confusion, tension, anger, cognitive anxiety, somatic anxiety, and self-confidence increased throughout the course whereas friendliness and SIgA secretion rate decreased (all p < 0.05). Compared to women, men had a greater acute increase in cortisol from pre- to post-match (p = 0.043). Prior to the final match, women displayed higher ratings of tension (20.5 ± 9.3 vs. 16.0 ± 8.6) and cortisol (0.6 ± 0.3 vs. 0.4 ± 0.3 µg/dL) than men (all p < 0.05). After controlling for previous combative experience, ratings of tension did not differ by sex but remained elevated prior to midterm and final compared to baseline. CONCLUSION Combatives training elicited significant psychological and physiological stress and decreased mucosal immunity in both men and women. Women exhibited higher tension at the final match, likely due to lack of previous combative experience. Self-confidence increased from baseline suggesting that the skills learned may help Cadets prepare for combatives and other activities that require controlled aggression.
Collapse
Affiliation(s)
- Meaghan E Beckner
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
| | - Jesse A Stein
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
| | - Mary R Lee
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
| | - Joseph J Knapik
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Emily K Farina
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Tracey J Smith
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Drew Van Dam
- United States Military Academy, West Point, NY, USA
| | | | | | - Harris R Lieberman
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA.
| |
Collapse
|
2
|
Hunter SK, S Angadi S, Bhargava A, Harper J, Hirschberg AL, D Levine B, L Moreau K, J Nokoff N, Stachenfeld NS, Bermon S. The Biological Basis of Sex Differences in Athletic Performance: Consensus Statement for the American College of Sports Medicine. Med Sci Sports Exerc 2023; 55:2328-2360. [PMID: 37772882 DOI: 10.1249/mss.0000000000003300] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
ABSTRACT Biological sex is a primary determinant of athletic performance because of fundamental sex differences in anatomy and physiology dictated by sex chromosomes and sex hormones. Adult men are typically stronger, more powerful, and faster than women of similar age and training status. Thus, for athletic events and sports relying on endurance, muscle strength, speed, and power, males typically outperform females by 10%-30% depending on the requirements of the event. These sex differences in performance emerge with the onset of puberty and coincide with the increase in endogenous sex steroid hormones, in particular testosterone in males, which increases 30-fold by adulthood, but remains low in females. The primary goal of this consensus statement is to provide the latest scientific knowledge and mechanisms for the sex differences in athletic performance. This review highlights the differences in anatomy and physiology between males and females that are primary determinants of the sex differences in athletic performance and in response to exercise training, and the role of sex steroid hormones (particularly testosterone and estradiol). We also identify historical and nonphysiological factors that influence the sex differences in performance. Finally, we identify gaps in the knowledge of sex differences in athletic performance and the underlying mechanisms, providing substantial opportunities for high-impact studies. A major step toward closing the knowledge gap is to include more and equitable numbers of women to that of men in mechanistic studies that determine any of the sex differences in response to an acute bout of exercise, exercise training, and athletic performance.
Collapse
Affiliation(s)
- Sandra K Hunter
- Exercise Science Program, Department of Physical Therapy, and Athletic and Human Performance Center, Marquette University, Milwaukee, WI
| | | | - Aditi Bhargava
- Department of Obstetrics and Gynecology, Center for Reproductive Sciences, University of California, San Francisco, CA
| | - Joanna Harper
- Loughborough University, Loughborough, UNITED KINGDOM
| | - Angelica Lindén Hirschberg
- Department of Women's and Children's Health, Karolinska Institutet, and Department of Gynecology and Reproductive Medicine, Karolinska University Hospital, Stockholm, SWEDEN
| | - Benjamin D Levine
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and the Department of Internal Medicine, Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Kerrie L Moreau
- Department of Medicine, Division of Geriatric Medicine, University of Colorado Anschutz Medical Campus, and Eastern Colorado Health Care System, Geriatric Research Education and Clinical Center, Aurora, CO
| | - Natalie J Nokoff
- Department of Pediatrics, Section of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, CO
| | - Nina S Stachenfeld
- The John B. Pierce Laboratory and Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT
| | - Stéphane Bermon
- Health and Science Department, World Athletics, Monaco and the LAMHESS, University Côte d'Azur, Nice, FRANCE
| |
Collapse
|
3
|
Charkoudian N, Lee JKW, Giersch GEW, DiPietro L, Stachenfeld N. Different perspectives on women's health, nutrition and endurance exercise. J Int Soc Sports Nutr 2023; 20:2286286. [PMID: 38018805 PMCID: PMC11018311 DOI: 10.1080/15502783.2023.2286286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 11/16/2023] [Indexed: 11/30/2023] Open
Affiliation(s)
- Nisha Charkoudian
- US Army Research Institute of Environmental Medicine, Thermal & Mountain Medicine Division, Natick, MA, USA
| | - Jason K W Lee
- National University of Singapore, Heat Resilience and Performance Centre, Yong Loo Lin School of Medicine, Singapore, Singapore
| | - Gabrielle E W Giersch
- US Army Research Institute of Environmental Medicine, Thermal & Mountain Medicine Division, Natick, MA, USA
| | - Loretta DiPietro
- The George Washington University, Department of Exercise and Nutrition Sciences, Milken Institute School of Public Health, Washington, USA
| | - Nina Stachenfeld
- Yale School of Medicine, John B. Pierce Laboratory, Obstetrics Gynecology and Reproductive Sciences, New Haven, CT, USA
| |
Collapse
|
4
|
Beckner ME, Thompson L, Radcliffe PN, Cherian R, Wilson M, Barringer N, Margolis LM, Karl JP. Sex differences in body composition and serum metabolome responses to sustained, physical training suggest enhanced fat oxidation in women compared with men. Physiol Genomics 2023; 55:235-247. [PMID: 37012051 PMCID: PMC10190831 DOI: 10.1152/physiolgenomics.00180.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/02/2023] [Accepted: 03/28/2023] [Indexed: 04/05/2023] Open
Abstract
Sex differences in energy metabolism during acute, submaximal exercise are well documented. Whether these sex differences influence metabolic and physiological responses to sustained, physically demanding activities is not well characterized. This study aimed to identify sex differences within changes in the serum metabolome in relation to changes in body composition, physical performance, and circulating markers of endocrine and metabolic status during a 17-day military training exercise. Blood was collected, and body composition and lower body power were measured before and after the training on 72 cadets (18 women). Total daily energy expenditure (TDEE) was assessed using doubly labeled water in a subset throughout. TDEE was greater in men (4,085 ± 482 kcal/d) than in women (2,982 ± 472 kcal/d, P < 0.001), but not after adjustment for dry lean mass (DLM). Men tended to lose more DLM than women (mean change [95% CI]: -0.2[-0.3, -0.1] vs. -0.0[-0.0, 0.0] kg, P = 0.063, Cohen's d = 0.50) and have greater reductions in lower body power (-244[-314, -174] vs. -130[-209, -51] W, P = 0.085, d = 0.49). Reductions in DLM and lower body power were correlated (r = 0.325, P = 0.006). Women demonstrated greater fat oxidation than men (Δfat mass/DLM: -0.20[-0.24, -0.17] vs. -0.15[-0.17, -0.13] kg, P = 0.012, d = 0.64). Metabolites within pathways of fatty acid, endocannabinoid, lysophospholipid, phosphatidylcholine, phosphatidylethanolamine, and plasmalogen metabolism increased in women relative to men. Independent of sex, changes in metabolites related to lipid metabolism were inversely associated with changes in body mass and positively associated with changes in endocrine and metabolic status. These data suggest that during sustained military training, women preferentially mobilize fat stores compared with men, which may be beneficial for mitigating loss of lean mass and lower body power.NEW & NOTEWORTHY Women preferentially mobilize fat stores compared with men in response to sustained, physically demanding military training, as evidenced by increased lipid metabolites and enhanced fat oxidation, which may be beneficial for mitigating loss of lean mass and lower body power.
Collapse
Affiliation(s)
- Meaghan E Beckner
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, United States
| | - Lauren Thompson
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - Patrick N Radcliffe
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, United States
| | - Rebecca Cherian
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - Marques Wilson
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - Nicholas Barringer
- Medical Center of Excellence, Joint Base San Antonio-Fort Sam Houston, Texas, United States
| | - Lee M Margolis
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - J Philip Karl
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| |
Collapse
|
5
|
MCCLUNG HOLLYL, SPIERING BARRYA, BARTLETT PMATTHEW, WALKER LEILAA, LAVOIE ELIZABETHM, SANFORD DIANAP, FRIEDL KARLE. Physical and Physiological Characterization of Female Elite Warfighters. Med Sci Sports Exerc 2022; 54:1527-1533. [PMID: 35621397 PMCID: PMC9390221 DOI: 10.1249/mss.0000000000002942] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION This study characterized a sample of the first women to complete elite United States (US) military training. METHODS Twelve female graduates of the US Army Ranger Course and one of the first Marine Corps Infantry Officers Course graduates participated in 3 d of laboratory testing including serum endocrine profiles, aerobic capacity, standing broad jump, common soldiering tasks, Army Combat Fitness Test, and body composition (dual-energy x-ray absorptiometry, three-dimensional body surface scans, and anthropometry). RESULTS The women were 6 months to 4 yr postcourse graduation, 30 ± 6 yr (mean ± SD); height, 1.67 ± 0.07 m; body mass, 69.4 ± 8.2 kg; body mass index, 25.0 ± 2.3 kg·m -2 . Dual-energy x-ray absorptiometry relative fat was 20.0% ± 2.0%; fat-free mass, 53.0 ± 5.9 kg; fat-free mass index, 20.0 ± 1.7 kg·m -2 ; bone mineral content, 2.75 ± 0.28 kg; bone mineral density, 1.24 ± 0.07 g·cm -2 ; aerobic capacity, 48.2 ± 4.8 mL·kg -1 ·min -1 ; total Army Combat Fitness Test score 505 ± 27; standing broad jump 2.0 ± 0.2 m; 123 kg casualty drag 0.70 ± 0.20 m·s -1 , and 4 mile 47 kg ruck march 64 ± 6 min. All women were within normal healthy female range for circulating androgens. Physique from three-dimensional scan demonstrated greater circumferences at eight of the 11 sites compared with the standard military female. CONCLUSIONS These pioneering women possessed high strength and aerobic capacity, low %BF; high fat-free mass, fat-free mass index, and bone mass and density; and they were not virilized based on endocrine measures as compared with other reference groups. This group is larger in body size and leaner than the average Army woman. These elite physical performers seem most comparable to female competitive strength athletes.
Collapse
Affiliation(s)
- HOLLY L. MCCLUNG
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
| | - BARRY A. SPIERING
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN
| | - P. MATTHEW BARTLETT
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
| | - LEILA A. WALKER
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
| | - ELIZABETH M. LAVOIE
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN
| | - DIANA P. SANFORD
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN
| | - KARL E. FRIEDL
- Military Performance Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA
| |
Collapse
|