I have one of those rings. I bought it because I like gadgets. I think I know what the author is getting at - it's nice to have a soulless device tell you yes, you aren't imagining it, you're having a down day. Take it easy on yourself.

The author's not talking about rest; they're talking about accepting tiredness.

Well what does that even mean if you don't follow that up with some good 'ol R&R?

But isn't that the core issue with "these" people: they have lost the ability to be able to interpret their body's sensations and warning signals and burn out as a result?

I'm not excempt from this. But the urge to substitute bodily awareness with sensory gadgets seems to gather religious proportions in some circles.

People can be surprisingly good at blocking out signals, especially when they have learned to regard a signal as broken and unhelpful.

Aron Ralston, the guy that 127 Hours is based on, in his memoir singles out a specific moment in his childhood when he decided to disregard his sense of fear, because it was paralyzing him and stopping him from doing normal things with his friends like skiing. Operating without regard for fear was obviously not a great fix. As an adult he lost friends who refused to go into the backcountry with him because he took irresponsible risks that put them in danger. Then he lost his arm.

People who struggle with depression have the same adversarial relationship with fatigue. When you spend much of your life struggling to force yourself to go when your brain says stop, you start to take a cynical attitude toward your sense of fatigue. It's a chronic liar, a stopped clock, the boy who cried wolf. On the other hand, once in a while it's telling the truth.

Anxiety can present as fatigue as well. When your brain is afraid of something, inducing a sense of fatigue is an easy way to avoid it.

When you can't trust your sense of fatigue, there's no simple rule for handling it. It's dangerous to ignore it, but on the other hand, you can't just trust it, because then you'd spend most of your life in bed. Maybe today the right answer is to "find joy in it" (barf) but tomorrow the right answer is to suck it up and work through it. There's no inspirational slogan that solves it. You just do your best to figure it out every day.

More people need to just work out. If you lift on a regular basis and you're having a day where you don't feel great, you'll know for certain very quickly if it's a "real" down day or not, without needing some special ring, because you'll miss lifts. It's somewhat true of cardio, too, but it's much more possible with extremely low energy output per rep exercise to just power through and do it. With strength training, you'll know for certain when your strength isn't there.

That sounds like a great system - for some people.