Sleep is the hidden hero of sustainable productivity. Long hours and even all-nighters can get you through temporarily (usually when you’re young) but you can’t rely on them long term. And their costs increase with every year of your life. Sufficient sleep, on the other hand, boosts your effectiveness tremendously. As part of your Health link, it amps the strength of every other link, improving your mood, your relations with others, your decision-making and planning, and so on.
Now there’s more evidence that it helps your body as well. Researchers have learned that people who get at least 7 hours of sleep get fewer colds than those who sleep less. Don’t have time for that much sleep? Do you really have time for the productivity deficits (and physical discomfort) caused by colds? Especially when the average non-senior adult gets 3 colds a year?