Researchers have just spoken out to say that taking a warm bath an hour or two before bedtime can help you get a better night’s sleep.

A team of biomedical engineers at The University of Texas at Austin used systematic review protocols to analyze thousands of studies linking water-based passive body heating, or bathing and showering with warm/hot water, with improved sleep quality. After looking at the data, they ended up concluding that bathing 1 to 2 hours before bedtime in water of about 104 to 109 degrees Fahrenheit (40 to 43 degrees Celsius) can significantly improve your sleep.

“When we looked through all known studies, we noticed significant disparities in terms of the approaches and findings,” said Shahab Haghayegh, a Ph.D. candidate in the Department of Biomedical Engineering. “The only way to make an accurate determination of whether sleep can in fact be improved was to combine all the past data and look at it through a new lens.”

The UT researchers teamed up with researchers at the UT Health Science Center at Houston and the University of Southern California to look at 5,322 studies. They focused on the effects of water-based passive body heating on the following sleep-related conditions: sleep onset latency (the length of time it takes to accomplish the transition from full wakefulness to sleep); total sleep time; sleep efficiency (the amount of time spent asleep relative to the total amount of time spent in bed intended for sleep); and subjective sleep quality.

They found that bathing in a bath that is 104 to 109 degrees Fahrenheit can hasten the process of falling asleep by an average of ten minutes. They also concluded that the best time to take a bath is 90 minutes before going to sleep. The research team has since teamed up with UT’s Office of Technology Commercialization to try to design a commercially viable bed system with UT-patented Selective Thermal Stimulation technology. This will allow the thermoregulatory function to be manipulated on demand and dual temperature zone temperature control that can be changed to maintain an individual’s optimum temperatures throughout the night.