Is this tiredness periodic? I experience something similar and my very weak suspicion is that it is non-24-hour sleep–wake disorder. Basically I start feeling tired even in the morning, but I am able to stay up all night without any problem. Going to bed late for a couple days seems to resolve it. Unfortunately I don’t know a good way to verify my hypothesis—I thought about measuring my base temperature to see how the peak shifts, but the device costs $300 and I have such tiredness only a couple times a year, so I didn’t bother.
That’s… a pretty good theory! Whenever I do achieve an early wake-up time, I have trouble holding on to it, quickly waking later until I run up against the “unacceptably late time to wake up” barrier. This is maybe consistent with an ever-advancing internal sleep-wake rhythm. It isn’t periodic in the way you describe your experience though.
Is this tiredness periodic? I experience something similar and my very weak suspicion is that it is non-24-hour sleep–wake disorder. Basically I start feeling tired even in the morning, but I am able to stay up all night without any problem. Going to bed late for a couple days seems to resolve it. Unfortunately I don’t know a good way to verify my hypothesis—I thought about measuring my base temperature to see how the peak shifts, but the device costs $300 and I have such tiredness only a couple times a year, so I didn’t bother.
That’s… a pretty good theory! Whenever I do achieve an early wake-up time, I have trouble holding on to it, quickly waking later until I run up against the “unacceptably late time to wake up” barrier. This is maybe consistent with an ever-advancing internal sleep-wake rhythm. It isn’t periodic in the way you describe your experience though.