nostr:npub13jdgzuwpwpsstpg03js8kp473wxek9ds6uff4vfv64rlv43pm5kss3uun7 >which is how the HR monitor judges whether you're asleep.
Sleep goes in 1.5 hour cycles, so if you miss the point when your body is ready and go to bed after midnight (say) you may be in the phase where your body is ramping back up again instead of winding down, making it harder to go to sleep.
I switched to going to be when my HR monitor thought I was already asleep, and within days I was going to sleep minutes after going to bed. Completely blown away.
HR monitor are better>