Circadian Blog Mr. Know-It-All Explains: A Hot Bath Can Improve Your Sleep

 Every little trick helps when you’re trying to get quality sleep in the day-time, whether it’s installing heavy-duty curtains or teaching your kids not to disturb you. One trick Mr. Know-It-All likes to indulge in before going to bed is taking a hot bath or shower. This technique is popular among many shiftworkers and research shows that it can improve your sleep. In a 1999 study at McLean Hospital in Belmont, Mass., researchers found that taking a hot bath (105 degrees F), 90-minutes before going to bed improved sleep efficiency. In the study, female insomniacs spent more time in Stage 3 and Stage 4 sleep — the deep “slow wave” sleep considered vital in order to wake up feeling well-rested — after taking a hot bath than they did after taking a bath in simply warm water.   The reason why sleep improved after taking a hot bath is not exactly clear. However, many sleep experts believe that the rise in body temperature during the hot bath followed by a rapid decrease in body temperature after taking the bath induces a feeling of sleepiness. For example, for people who are day-oriented (such as those working a string of day shifts), their body temperatures drop significantly at night. Thus, the effect after a hot bath mimics this similar drop in temperature that people experience at night. So, if you’re having trouble sleeping, you may wish to add a hot bath (or a hot shower) to your post-night shift, pre-sleep routine. If your family thinks you’re pampering yourself, tell them you’re doing your own experiment with “passive body heating” — that’s what the researchers call hot baths. Looking for more Working Nights Tips, subscribe to our Working Nights Newsletter. Download our latest whitepaper: New 2019 Analysis: The Pros & Cons of 12-Hour Shifts