Skip to main content

Physiological Reserve Index

Meaning

The Physiological Reserve Index is a clinical metric or composite score that quantifies an individual’s latent capacity for maintaining systemic homeostasis and recovering from acute physiological stressors, such as illness, injury, or intense physical exertion. It represents the functional margin between the normal operational state and the threshold of clinical decompensation or failure across multiple organ systems, including cardiovascular, metabolic, and neuroendocrine axes. A higher index is directly correlated with greater resilience, improved healthspan, and reduced all-cause mortality risk.