Evidence map›Paper›PMID 42859185›Full record

ArticleEuropean journal of applied physiology2026

Endocrine dynamics of special operations forces across mission cycles: implications for human stress physiology.

William J Kraemer, Mark D Stephenson, Jeff S Volek, Tunde K Szivak, Catherine Saenz, Shawn D Flanagen, Elaine C Lee, Nicholas A Ratamess, Emily M Post, Lydia K Caldwell and 3 more

Abstract read
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In one paragraph

Article in European journal of applied physiology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0cells of the map it votes in
0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors.

William J KraemerDepartment of Human Sciences, The Ohio State University, Columbus, OH, USA. William.Kraemer@uconn.edu.ORCID http://orcid.org/0000-0002-6907-0264
Mark D StephensonTactical Sports Science Innovations, Hope Valley, RI, USA.
Jeff S VolekDepartment of Human Sciences, The Ohio State University, Columbus, OH, USA.
Tunde K SzivakSchool of Nursing and Health Sciences, Merrimack College, North Andover, MA, USA.
Catherine SaenzDepartment of Human Sciences, The Ohio State University, Columbus, OH, USA.
Shawn D FlanagenDr. William M. Scholl College of Podiatric Medicine, School of Graduate and Postdoctoral Studies, Rosalind Franklin University, North Chicago, IL, USA.
Elaine C LeeDepartment of Kinesiology, University of Connecticut, Storrs, CT, 06269, USA.
Nicholas A RatamessDepartment of Kinesiology and Health Sciences, The College of New Jersey, Ewing, NJ, USA.
Emily M PostDepartment of Health & Sport Sciences, Otterbein University, Westerville, OH, USA.
Lydia K CaldwellDepartment of Health and Sports Science, University of Dayton, Dayton, OH, USA.
Alex BugaDepartment of Human Sciences, The Ohio State University, Columbus, OH, USA.
Joshua A HagenOffice of Research, Human Performance Collaborative, The Ohio State University, Columbus, OH, USA.
Carl M MareshDepartment of Human Sciences, The Ohio State University, Columbus, OH, USA.

Funding

Defense Sciences Office, DARPA W911NF-13-1-0030
6 · The paper itself

Abstract

purposeThis study investigates the endocrine responses and muscle damage markers in elite male Special Operations Force operators across operational phases to understand hormonal adaptations to extreme operational stress and recovery.

methodsFifty-six operators (28-42 years) participated in a longitudinal study conducted at a Special Operations Forces unit. Blood samples were collected at three visits: Visit 1 (baseline recovery), Visit 2 (intensive pre-deployment training), and Visit 3 (post-deployment recovery). Serum concentrations of testosterone (T), cortisol (CORT), dehydroepiandrosterone sulfate (DHEA-S), growth hormone (GH), insulin-like growth factor-I (IGF-I), progesterone (P4), creatine kinase (CK), and myoglobin (Mb) were analyzed.

resultsPost-deployment (Visit 3), T levels increased (+ 20%, p < 0.05), and CORT decreased (- 23%, p < 0.05), resulting in a significantly higher testosterone-to-cortisol ratio compared with Visit 1 and Visit 2 (p ≤ 0.05). DHEA-S correlated with CORT (r = 0.37, p < 0.05), suggesting a compensatory adrenal response under stress. GH concentrations were markedly reduced post-deployment (- 84%, p ≤ 0.05), while IGF-I remained stable, indicating differential regulation within the GH-IGF-I axis during recovery. P4 concentrations remained elevated across all phases, reflecting a consistent endocrine feature across operational phases rather than a defined mechanistic adaptation. No significant changes were observed in CK or Mb, underscoring effective physical stress management at the time of post-deployment sampling.

conclusionThese findings emphasize the importance of tailored training and recovery strategies for sustaining endocrine balance, resilience, and operational readiness in elite military personnel.

Indexed as

AnabolicCatabolicHormonesMilitaryMuscle damage

Identifiers

PMID42859185

What OpenQuestion holds

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.