A lot of that is sleep hygiene. People rarely had issues falling asleep early before electrification. And we’ve made it even worse with TV, computers and smartphones. Being very conscious of light consumption and turning off devices several hours before sleep makes it pretty easy to fall asleep earlier.

I’m one of those people who normally can’t fall asleep before midnight and struggles to wake up early, but I’ve done a few digital detox programs where I’m without any electronic devices, and I’m always amazed at how quickly I fall into a schedule where I’m asleep before 9 and waking up at 4:30. And it’s also amazing how much better I feel both mentally and physically when I’m on that schedule.