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They skip naps
"One thing that most surprises patients is when I tell them to avoid taking naps, even if they were unable to sleep the night before," says Damon Raskin, MD, a board-certified internist who specializes in sleep medicine. A midday snooze decreases your "sleep drive" (or the sleepiness you build up during the day), making falling asleep at bedtime later that night even harder. That can set off a sleeplessness cycle that you don't want to get wrapped up in. If you're lagging during the day, skip the caffeine (which only will keep you up at night) and power through with a walk outside: Spending at least 20 minutes outside with nature has been shown to give people a mental and physical energy boost.