What are some good unit, integration, performance tests for human beings?
What prompted this was I started training for a triathlon and thought of myself as a healthy, fit person, able to run a 5k at a decent pace. However, I've been amazed to find out how much my aerobic fitness has cratered over the last couple years of working at home (no more cycling to work) and I'm unable to train for the required 3-4 hours per week at low intensities because I'm so aerobically unfit and muscularly weak. I see this as me passing a unit test (able to run 5k at intensity) but failing an integration/performance test (unable to string together long periods of training). Bringing this into sharper focus is that I've learned that this exact amount of training (3-4 hours of zone 2 training per week according to Peter Attia) is the recommended dose of exercise for a long health span, making me wonder what other aspects of my life are quietly failing due to me not having a test and benchmark to measure against.
Would love to hear of various objectiv-ish ways to evaluate a person's abilities in important aspects of life: fitness/health/strength, finances, mental health, relationships. I'm not looking for 100% test coverage here, this is merely an attempt to catalogue the important parts of our life and the ways to observe them over the long term.