Like to unwind in the tub before you snooze? Surprisingly, a hot bath might make it harder for you to drift off: Doing anything that raises your body temperature too close to bedtime may actually hinder you from falling asleep, because your body needs to cool to a certain temperature in order to reach a sound slumber, says J. Todd Arnedt, PhD, director of the University of Michigan Behavioral Sleep Medicine Program. That doesn’t mean you can’t soak after a rough day—when you get home from work, not right before turning in.