Resilience is commonly framed as a psychological trait, yet clinical and experimental evidence demonstrates that resilience failures emerge concurrently across metabolic, endocrine, immune, and cognitive domains. This review examines resilience as a bioenergetic property constrained by how organisms allocate finite metabolic resources under stress. We synthesize evidence from endocrinology, mitochondrial biology, immunometabolism, and stress physiology to propose a parsimonious, hypothesis-driven Energy Allocation System (EAS) in which the hypothalamic-pituitary-adrenal (HPA), thyroid (HPT), and gonadal (HPG) axes are conceptualized as a coordinated energy-governance network. Despite extensive investigation within these individual fields, the literature lacks an integrative physiological framework explaining why multisystem stress responses co-occur in predictable endocrine and metabolic patterns. Within this framework, mitochondrial reserve capacity serves as the limiting substrate through which hormonal signals regulate mobilization, metabolic pacing, immune tolerance, and recovery. The reviewed literature supports predictable patterns of endocrine reorganization during energetic strain, including prioritization of glucocorticoid-mediated mobilization, constrained thyroid hormone activation, suppression of long-term anabolic investment, and impaired recovery following stress. These configurations reflect adaptive energy-conserving strategies rather than isolated organ dysfunction. The novelty of this review lies in organizing established biological mechanisms into a unified, energy-allocation-based framework that generates falsifiable predictions linking endocrine coordination to bioenergetic capacity and recovery dynamics. We further discuss how routinely available biomarkers and validated psychometric measures can be interpreted as functional readouts of energetic allocation rather than static disease markers. Framing resilience through coordinated energy governance offers a unifying mechanistic lens for interpreting multisystem stress responses and generates testable predictions for future experimental and clinical investigation.
Schuler et al. (Thu,) studied this question.