Recent research has uncovered significant health benefits associated with just one additional hour of sleep each night among college students. The small study, published in Sleep Health, found that extending sleep duration by an hour resulted in decreased sleepiness, lower blood pressure, improved glucose regulation, and better hydration, offering new insights into the widespread benefits of adequate sleep for young adults.
The idea that a good night’s sleep is essential for health is not new, but the specific impacts of extending sleep duration, particularly among young adults, have been less clear. Previous research has established a link between short sleep duration and various health issues, including high blood pressure, increased heart rate, and lower physical activity levels. College students, with their unique schedules and lifestyle, often experience disrupted sleep patterns, making them an ideal demographic for studying the effects of sleep extension.
“There have been some studies showing that young adults with short sleep duration (<7 hours/night, the minimum recommended duration by the American Academy of Sleep Medicine for optimal adult health and wellbeing) report feeling sleepy and have poor physical health, including higher systolic blood pressure and heart rate, higher hemoglobin A1C, and lower levels of physical activity,” explained study author Gina M. Mathew (@GinaMMathewPhD), a postdoctoral associate in public health at Stony Brook Medicine.
“There is a lack of research that examines whether attempting to lengthen sleep is feasible in college students, a population that’s at high risk for insufficient sleep, and whether such a sleep extension intervention would improve physical health. We therefore examined effects of a 1-week, 1-hour nightly sleep extension intervention in a sample of 12 college students on cardiac and metabolic parameters, physical activity, and hydration levels.”
The study’s sample was predominantly female, aged 18-23 years, and had an average Body Mass Index of 24.5. Participants were in good physical and mental health, and those with sleep disorders, cardiometabolic diseases, or on certain medications were excluded to isolate the effects of sleep extension.
Over two weeks, the study followed a rigorous protocol. The first week served as a baseline, where participants maintained their usual sleep habits. In the second week, they were instructed to extend their sleep by one hour each night. The researchers monitored sleep patterns using actigraphy watches and measured physical activity with hip-worn accelerometers. Blood pressure, heart rate, and metabolic responses to a standardized meal were recorded in laboratory visits. Additionally, urine samples were analyzed for hydration status, and participants completed the Epworth Sleepiness Scale, a measure of daytime sleepiness.
On average, participants increased their sleep duration by about 43 minutes per night. This seemingly small change led to a notable decrease in self-reported sleepiness. More surprisingly, participants showed a significant decrease in systolic blood pressure – a key marker of heart health. The study also found that the time it took for participants’ blood glucose levels to return to baseline after a meal was shorter, indicating improved glucose regulation – a vital factor in managing and preventing diabetes.
Another fascinating outcome was the improvement in participants’ hydration status. Measurements showed significant reductions in urine osmolality and specific gravity, suggesting better hydration. This finding is particularly important, as proper hydration is crucial for various bodily functions, including kidney and cognitive performance.
“College students can indeed extend their sleep significantly; across a week, college students in our sample lengthened their sleep by an average of 43 minutes/night,” Mathew told PsyPost. “Moreover, compared to their typical sleep, sleep extension resulted in less reported sleepiness, better physical health (lower systolic blood pressure, lower glucose levels and faster time for glucose to return to baseline levels after a meal, and lower levels of dehydration), and lower levels of sedentary activity.”
The study’s findings are significant as they suggest that even a modest increase in sleep duration can have multiple health benefits for young adults, a demographic often prone to sleep deprivation. The improvements in blood pressure and glucose regulation are particularly noteworthy, given their implications for long-term heart health and diabetes risk.
However, the study is not without its limitations. The small sample size and the lack of a randomized design mean that these findings need to be replicated in larger, more diverse populations to confirm their validity. Additionally, the researchers observed a decrease in physical activity levels during the sleep extension week, which raises questions about the potential trade-offs between increased sleep and physical activity, an important area for future research.
“The sample size was small and limited to healthy young adults, so we can’t make broad generalizations to the larger population,” Mathew said. “Additionally, we found that levels of moderate-to-vigorous physical activity (MVPA) decreased during the sleep extension week, suggesting that exercise may have been sacrificed for increased sleep. Interestingly, we saw the improved physical health metrics after the sleep extension despite this reduction in MVPA!”
“Questions for future studies: Would a longer sleep extension intervention (e.g., one month) be feasible? What incentives and/or strategies would promote sustained sleep extension in different populations (e.g., college students, working adults, the retired, etc.)? What strategies would work to boost both sleep duration AND MVPA? Would our results apply to older adults and/or those with chronic diseases?”
“The principal investigator of the study is Dr. Anne-Marie Chang, with whom I received my doctoral degree at Penn State,” Mathew added. “I’m so thankful for her and the rest of our Penn State team, and I’d especially like to acknowledge Rodney Jones for his dedication to the planning and running of this study.”
The study, “Effects of a 1-hour per night week-long sleep extension in college students on cardiometabolic parameters, hydration status, and physical activity: A pilot study“, was authored by Gina Marie Mathew, Nicole G. Nahmod, Lindsay Master, David A. Reichenberger, Asher Y. Rosinger, and Anne-Marie Chang.
