Last night we got to bed late, so I was yawning through the individual presentations the students were doing today. That's really not fair to them. I can't judge them as well. I couldn't do my best, because I hadn't taken care of the stewardship of my body like I should have. That has consequences. That doesn't mean we indulge ourselves, be lazy, or refuse to do good things. It means we need to learn what it takes for our bodies to be at their optimum, balancing it of course with responsibilities and time.
The point is, when I eat right, sleep enough, exercise sufficiently, and keep up a balanced amount of cleanliness, I can do more! I become more worthwhile/valuable! Those all require attention to learn how to do, but they pay rewards in how effective we can be.