Winter-Proof Your Workout

Winter Woe: You can't get out of bed on dark mornings to do your a.m. workout.

Fix-it trick: Tuck in earlier to go from tired to inspired. "Darkness is a cue for your brain to crank out the sleep-inducing chemical melatonin," says Alfred Lewy, MD, a sleep and mood disorder researcher at Oregon Health & Science University in Portland. "In the winter, when you wake up before sunrise, it's like having jet lag -- for four or five months," Lewy says. If it's not possible to wait for the sun to sneak in your workout when you're more energized, he suggests making your wake-up easier by going to bed 15 minutes earlier each week over the next four weeks: Set your cell phone alarm for when it's time to hit the sack at night and avoid computer and TV use for an hour before bedtime to shut out light and other brain stimulators. That extra hour of shut-eye could make a huge difference in your morning-after mood: Brazilian researchers randomly assessed 200 healthy people and found that night owls, who went to sleep at midnight, were almost three times more likely to experience severe symptoms of depression than those who turned in at 11 p.m.