From The Energy Project: Our most funda­mental need as human beings is to spend and renew energy. Instead, in a world of relent­lessly rising demand and chronic over­drive, most of us spend far more mental and emotional energy than we adequately renew, and far too little phys­ical energy to stay fit.

The average Amer­ican gets just over 6 ½ hours of sleep a night. In fact, more than 95 percent of us need between 7 and 8 hours to feel fully rested. Great performers, from musi­cians to athletes, average as much as 8 ½ hours of sleep a night.

It’s during sleep — deep, suffi­cient sleep — that our bodies not only renew and recharge, but also repair them­selves and grow. · Go to How to recover your core rhythm →