Training for health...
It's not necessarily the same as training for performance.
When health is the focus you don't want to overly tax the body into deep soreness and fatigue.
Training should always be invigorating never creating excessive soreness.
This doesn't mean you shouldn't be improving.
You should.
But don't push so hard that the immune system is suppressed.
Training causes inflammation and the removal of damaged cells.
It's a similar response to fighting a pathogen.
For this reason, we don't want to be causing massive damage and removing damaged cells from the body in competition with the removal of pathogenic cells.
Heart Rate Variability, morning freshness, grip dynamometer, jump height, desire to train, appetite are all measures that can tell us about our recovery and how hard training has been.