What is the Origin of Physiological Load?

This is a conceptual term derived from the more clinical concept of "allostatic load," which was introduced in the 1990s by Bruce McEwen and Eliot Stellar. Allostasis means 'achieving stability through change,' and the load refers to the cost of this chronic adaptation. "Physiological Load" offers a more accessible term for the total biological cost of living and adapting.

What is the Mechanism of Physiological Load?

When the body perceives a stressor, the HPA axis and the sympathetic nervous system are activated, leading to the release of mediators like cortisol and adrenaline. While acute release is adaptive, chronic, repeated, or poorly terminated stress responses lead to prolonged exposure to these mediators. This prolonged exposure causes wear and tear on cardiovascular, metabolic, and immune systems, resulting in tissue damage and dysregulation that constitute the high physiological load.

Physiological Load

Meaning

The cumulative burden placed upon the body’s homeostatic systems by the total sum of all internal and external stressors, encompassing physical, psychological, metabolic, and environmental demands. This metric reflects the ongoing effort required by the body to maintain stability, or allostasis, in the face of these challenges. A consistently high load can deplete adaptive reserves and accelerate the rate of cellular aging.