In my experience and based on available research, we naturally go through stages of life that begin with exponential growth.
Challenge
Recovery
This corresponds to two branches of the peripheral nervous system: sympathetic and parasympathetic.
Cycles occur for each of three domains of our outer world that impact our inner life:
Relational
Occupational
Nutritional
These are correlated with the central, peripheral, and enteric nervous systems, respectively.
Voluntary challenge and deliberate recovery with optimal resources results in:
Operational Stability.
The CRONOS Framework
Small, steady improvements across all three life domains—Relational, Occupational, and Nutritional—build overall resilience.
Challenging ourselves is inherently voluntary; this triggers recovery, which increases our baseline. Our intent to challenge triggers our sympathetic nervous system. The input is our activity. The effects of the challenge, will trigger the underlying process parasympathetic nervous system, and the resulting output is greater resilience. It is easier on the body to do this by choice than by circumstance; thus the stress is perceived as beneficial.
The CRONOS Operational-Stability (OS) score captures this in a single number. If even one domain is neglected, the total dips, showing us exactly where to focus next.
In order to thrive, we must choose our challenges before our challenges choose us. Recovery improves with the right resources for recovery.
Of course, all this is governed by somatic nervous system, which is the Relational | CNS, but for simplicity we focus on how we can apply this basic physiological feedback loop for our benefit.
The CRONOS Framework is based on multiple lines of evidence in physiology and neuroscience. The biological principle of allostasis shows that stability is achieved through change.

Choose your challenge: the cycle of voluntary challenges while ensuring adequate recovery ensures people like you and I can harness our body’s natural adaptive mechanisms.
Example: any challenge to our thinking and feeling will naturally create a sense of stress; it is perceived the same as physical stress, like exercise. So we can expand our comfort zone to create change incrementally. This is true when we challenge ourselves to expand and/or deepen our social circle, focusing on our greatest and most important relationships, to strengthen them.
A systematic method will ensure no domain goes unfulfilled
Challenge + Recovery Scoring
An equation that we can use to gauge our quality of life:
