Aug. 13, 2019&mdash;Seeking a good night's slumber? A relaxing bath or shower just might improve your snooze. But it matters when you hit the tub before you hit the pillow. And it's also important to have the best sleep-promoting water temperature, according to the results of a new study.
Researchers analyzed the results of 13 previous studies about bathing and showering and better shuteye. Here's what they discovered: 
<ul>
 <li>The best time for taking a warm or hot bath or shower is about 90 minutes before you go to bed. But bathing anywhere from one to two hours before bedtime could help you fall asleep more quickly. It could shave about 10 minutes off the time it takes you to fall asleep. </li>
 <li>The ideal water temperature to improve overall sleep quality is about 104 to 109 degrees. </li>
</ul>
Body temperature, water and sleep: What's the connection?
When you feel awake or sleepy is controlled, in part, by your circadian rhythm. That's a built-in 24-hour biological alarm clock we all have. That clock is controlled by the brain and influenced by other factors, like light and darkness. Body temperature also plays a role in sleep and wakefulness. And, as it turns out, it follows a circadian cycle too. 
According to the authors of this study, the body's core temperature is higher when we're awake than when we're asleep. It drops about an hour before our usual bedtime, which helps us fall asleep. Body temperature begins to rise again near the end of the night, which helps us wake up. 
Surprisingly, warm bathing helps the body cool down for better sleep. The warm water causes blood to move outward from the body to the hands and feet, which causes the body to lose core heat. This is how a well-timed bath or shower enhances the body's natural circadian cycle, according to the researchers. 
That study appeared in the journal Sleep Medicine Reviews.
Uncovering a serious sleep problem
Ongoing sleep problems can often be diagnosed in an overnight sleep study. Curious about what happens in a sleep lab? <a href="[BASEDOMAIN]/healthinfo/Story.aspx?StoryID=f5ac7130-ed63-42ab-a819-4a8ea13f6ea2">Read this story to find out</a>.

Bathing before bedtime can improve sleep