Whereas homeostasis is the body's attempt to keep vital signs within a very tight, static range, allostasis is the active process of adaptation. Allostatic load is the body's running total of stress. Every challenge - a hard training ride, poor sleep, work pressure, illness, travel, even emotional strain - triggers stress systems whose purpose is to adapt and reach a 'new normal'. Provided the stress doses are manageable, this is a healthy process.
It's how you adapt and get fitter. "While allostasis is the healthy process of the body changing its internal state to match external demands- such as your heart rate rising during a steep climb - allostatic load is the physiological price the body pays for that adaptation over time," says Professor Sebastian Sitko.
