This scoping review, authored by Ashley M. Welsh, Jason L. Judkins, Kristin J. Heaton, and Mary A. Steinhardt, provides a comprehensive examination of the influence of psychological hardiness on the health outcomes of military personnel. Published online on May 24, 2025, in The Journal of Positive Psychology, the article analyzes forty-eight studies published between 1990 and 2025. The review specifically utilizes the U.S. Army’s Holistic Health and Fitness (H2F) framework, which integrates five core health domains: mental, physical, sleep, nutritional, and spiritual health. This framework represents a significant shift in military readiness strategy from a sole focus on physical health to a more comprehensive, holistic approach.
The article highlights that military personnel face unique, high-stress environments that significantly impact their health, citing statistics such as over 1.4 million physical injuries in 2021, a 10% increase in mental health diagnoses in 2021, and substantial increases in sleep disorders and obesity. The need for holistic preventive strategies is underscored due to the interdependence of these health concerns.
Key Concepts and Findings:
The review establishes psychological hardiness as an important modifiable factor that enables individuals to effectively manage elevated stress levels without succumbing to illness or injury. Hardiness is defined by three core components:
- Commitment: A tendency to fully engage in life activities, find meaning, and maintain curiosity.
- Control: The belief that one’s actions can influence events and outcomes.
- Challenge: A positive attitude toward change and new experiences, viewing them as opportunities for growth rather than threats.
The analysis of the 48 studies consistently demonstrates a robust association between higher levels of hardiness and enhanced health outcomes across all five H2F domains:
- Mental Health: Forty-one studies focused on this domain, showing that higher hardiness scores were consistently associated with lower levels of anxiety, depressive symptoms, posttraumatic stress disorder (PTSD), and alcohol at-risk use and abuse. Hardiness was also linked to lower psychological distress and higher psychological well-being. Notably, hardiness appeared to buffer the effects of deployment stressors on depression and weakened the association between prolonged military service and PTSD symptoms.
- Physical Health: Higher hardiness was significantly associated with fewer health symptoms, healthier behaviors (e.g., physical activity, condom use), lower rates of physical illness, and fewer injuries. However, the protective effects of hardiness against deployment-related or chronic stress on physical health appeared limited, possibly due to the intense physical wear and tear in such environments.
- Sleep Health: While only two studies were found, higher hardiness levels were associated with reduced insomnia symptoms during a naval mission. However, hardiness was not significantly correlated with overall sleep quality, potentially due to other influencing factors like environmental conditions.
- Spiritual Health: Hardiness showed a significant positive association with religiosity, spiritual readiness, and spiritual performance. This suggests a link to a strong sense of purpose, guiding values, and inner resources.
- Nutritional Health: One recent study found that hardiness was negatively associated with symptoms of eating disturbance and disorder. It also demonstrated a buffering effect against the increase in eating disorder symptoms associated with greater stress.
The review further explains that hardiness influences health outcomes through mediating factors, primarily adaptive coping strategies and a lower reliance on avoidance coping. High-hardiness individuals tend to interpret stressors as less threatening, which leads to lower perceived stress and healthier, task-focused or problem-focused coping styles. Coping self-efficacy, or confidence in managing stress, was also identified as a critical mediator. Additionally, hardiness frequently acted as a moderating factor, protecting military personnel from the adverse impacts of combat-related and nontraumatic stressors on mental and nutritional health.
Limitations and Future Research:
Despite the valuable insights, the review identifies several limitations in the existing research:
- Methodological Gaps: Most studies were cross-sectional (63%), which limits the ability to infer causality. There is a notable absence of intervention studies specifically designed to enhance hardiness and health outcomes.
- Under-explored Domains: Research on hardiness’s influence on sleep, nutritional, and spiritual health remains limited compared to mental and physical health.
- Sample Diversity: A significant portion of studies used male-only samples or predominantly male samples (>70% male), limiting the understanding of sex differences in hardiness’s influence on health.
- Measurement Variability: Nine different hardiness measures were used across the studies, leading to variations in how hardiness is operationalized and making robust comparisons challenging.
The authors conclude that future research should prioritize rigorous, longitudinal, and intervention-based methodologies to clarify causal pathways and inform potential applications. They suggest that targeted interventions to enhance hardiness could offer wide-ranging benefits, particularly within existing programs like H2F, by promoting adaptive coping strategies, coping flexibility, adaptability, and self-efficacy. Expanding research into the under-explored health domains is critical for developing comprehensive strategies to optimize the holistic health and readiness of military personnel. The findings may also have implications for civilian health promotion efforts in high-stress environments.
Reference: Welsh, A. M., Judkins, J. L., Heaton, K. J., & Steinhardt, M. A. (2025, May 24). The influence of hardiness on health outcomes in military personnel: A scoping review. The Journal of Positive Psychology. https://doi.org/10.1080/17439760.2025.2509982.