I Woke Up Tired for 10 Years. Then I Learned About 90-Minute Cycles.

The Night Everything Changed

It was 3:47 AM. I was holding my son, rocking him back to sleep, and staring at my own reflection in the dark window. I had a PhD in Behavioral Neuroscience. I had spent six years in a sleep lab at CU Boulder. And I had not slept through the night in fourteen months.

The next morning, I pulled out my old lab notebooks. I found the data we had collected on ultradian rhythms — the 90-minute cycles that govern not just sleep, but alertness, creativity, and mood. I realized I had been setting my alarm at the wrong point in my cycle for a decade.

That is when I built the first version of the Sleep Cycle Calculator. For myself. Then my husband started using it. Then my mom. Then my mom's book club. Now it is here for you.

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