Rule #6: Sleep at least 7.5 hours per night

Health

Dec 26

The utility of sleep is multi-faceted: it clears metabolic byproducts from the brain, reinforces the neurological circuits involved in learning and memory, mitigates stress, and enables physical recovery from injury and exercise.

Perhaps more immediate, absence of sleep leads to decreased cognitive function, slow healing, and if it persists long enough, death.

Accordingly, sleep is the protector and servant of our bodies and brains, taking its place alongside exercise and diet as a primary arbiter of healthspan, and by extension, our ability to develop Agency and Impact.

Sleep is composed of 90-minute cycles of deep, light, and REM (rapid eye movement) sleep stages, each of which is characterized by specific brainwave forms and physical correlates.

REM stage sleep, thought to consolidate learning and memory, occurs toward the end of these cycles, and is most similar to full wakefulness in its brainwave patterns, making it desirable to wake immediately following REM sleep for maximum alertness and productivity. Our recommendation of 7.5 hours is 5 complete sleep cycles — an endpoint that will allow a smooth transition into non-groggy wakefulness.