Reading an article about 1.5-hour sleep cycles and going to bed earlier. The article said, that your circadian rhythm works roughly in 90 minute increments, sin

Reading an article about 1.5-hour sleep cycles and going to bed earlier. The article said, that your circadian rhythm works roughly in 90 minute increments, since then I set my alarm for 6 or 7.5 hours (9 if I’m extremely exhausted for some reason). I don’t know if that’s placebo, and I don’t care, but it worked for me in a way 8h of sleep never did. While I was getting used to it, I was also getting tired earlier. So everything moved a bit towards earlier times, and I’ve stayed with that. That change happened around 4-6 years ago.