Psychological and physiological changes during basic, underwater, demolition/SEAL training
Level 3 - non-randomized controlled study
Prospective longitudinal cohort study evaluating changes over time without an unexposed control group.
OpenAlex W4297322582 · doi:10.1016/j.physbeh.2022.113970
What was done
Researchers followed 353 U.S. Navy SEAL candidates across three classes during a six-month assessment and selection course. Data were collected at four timepoints across the training period. Psychological traits were evaluated using resilience, hardiness, and grit instruments. Blood samples were collected to measure physiological stress markers: DHEA, DHEA-to-cortisol ratio, BDNF, NPY, and cortisol.
What was found
Resilience and hardiness increased after an initial decline. Physiologically, DHEA and the DHEA-to-cortisol ratio increased over time. The abstract reports no numerical values, effect sizes, confidence intervals, or specific statistical findings for BDNF, NPY, cortisol, or grit, but notes that psychological and physiological markers showed differing growth patterns.
Why it matters
It provides longitudinal tracking of human psychological and endocrine adaptation under sustained, extreme environmental and physical stress.
Limits
The abstract provides no numerical data, baseline values, or p-values. The sample comprises a highly select group of military recruits, limiting generalizability to broader populations. There was no unexposed control group, and attrition rates across the six-month course were not reported.
Cited by
- context A standard BUD/S class starts with over 200 candidates and finishes with fewer than 20 graduating.