What’s the best time to exercise? When you can fit it in—even if that’s right before bed. You may have heard that exercising at night can make it harder to fall asleep, but that claim doesn’t add up: According to the National Sleep Foundation, a study of 1,000 people found that there were no significant differences in sleep quality between people who exercised within four hours of going to sleep versus those who had worked out earlier in the day. No matter what time of day you exercise, you’ll likely sleep better: In the National Sleep Foundation study, 83 percent of “vigorous exercisers” got “very good” or “fairly good” quality of sleep, compared to just 56 percent of non-exercisers. And working out before bed could actually improve your sleep quality further: In a review of 23 different studies, published in Sports Medicine , people who exercised within four hours of bedtime had more hours of deep sleep than those who didn’t do those workouts, says RunnersWorld.com. Getting qualit...