Recent analysis of pilot studies focused on night shift naps has deduced that taking two distinct naps—a 90-minute session before midnight followed by a 30-minute session during the early hours—substantially combats drowsiness and fatigue more efficiently than one prolonged nap. These insights are pertinent to professionals like healthcare workers and could also be invaluable to new parents, emphasizing the significance of nap timing and distribution to preserve alertness and productivity.
A detailed examination of pilot studies on night shift napping from 2012 to 2018 has uncovered a nap regimen that can counter sleepiness and fatigue over a demanding 16-hour night shift. These conclusions are also applicable to new parents.
Data reevaluation revealed that for those pulling an all-nighter, organizing two separate naps—a 90-minute one, followed by a shorter 30-minute one—surpasses the benefits of a single 120-minute nap in warding off fatigue and sleepiness. The journal Scientific Reports recently published these findings.
Sanae Oriyama, the sole researcher and a professor of nursing science at Hiroshima University’s Graduate School of Biomedical and Health Sciences, commented that a strategic combination of a 90-minute nap to maintain sustained performance and a 30-minute nap to uphold reduced fatigue levels and swift reactions proves invaluable for early morning work efficiency and safety.
Night shifts are standard in emergency domains such as healthcare, where continuous service can be vital. Medical professionals often undertake double shifts during unconventional hours. However, night shift duties can elevate the risk of sleep-associated health issues and deteriorate work performance.
Our internal clock, which is sensitive to light, triggers wakefulness during the day and lessens alertness at night, which increases the chances of mistakes. In medical settings, this could inadvertently result in severe consequences for patients. To counteract this, shift workers frequently resort to napping.
In Japan, during 16-hour night shifts, nurses are usually permitted to sleep for up to two hours. Oriyama sought to determine the most effective nap routine to combat fatigue and cognitive decline during such demanding hours, while also exploring sleep quality.
She revisited previous pilot studies she had collaborated on to compare wakefulness and cognitive efficiency post-nap during a simulated 4 p.m. to 9 a.m. shift. The experiments explored conditions of no nap, one nap, and two naps.
Those who took a single 120-minute nap reported heightened drowsiness by 4 a.m. that persisted till shift end. Conversely, participants who opted for two naps—90 minutes concluding at midnight and 30 minutes ending at 3 a.m.—managed to delay fatigue till 6 a.m. To tackle potential drowsiness between 7-8 a.m., Oriyama advised an additional 30-minute nap between 5-6 a.m.
Regarding fatigue, while all nap groups reported significant levels between 4-9 a.m., the intensity was noticeably lower for those in the two-nap category.
During a typical night shift spanning 4 p.m. to 9 a.m., Oriyama posits that a divided nap—90 minutes and 30 minutes concluding at midnight and 3 a.m., respectively—is superior to a single 120-minute nap when tasks demand prompt responses between 2 a.m. and 9 a.m.
While both singular and divided nap strategies did not enhance cognitive task outcomes, Oriyama observed that those struggling to fall asleep during the 90-minute nap performed poorly on the Uchida-Kraepelin test (UKT), an exam assessing speed and precision in a task. The study also highlighted that if sleep duration extends, fatigue and drowsiness might escalate.
Prior studies have shown that a 30-minute nap can enhance alertness, vigilance, and energy. Furthermore, the timing of the nap is crucial: delaying it can combat fatigue more effectively, but excessive postponement can diminish concentration.
Oriyama believes that her findings could assist new parents in managing sleep deprivation.
The research comprised 41 female participants in their 20s. They were invited to a controlled environment mimicking a 16-hour night shift. Various parameters, such as temperature, light, and sleep settings, were standardized, and participants were monitored for different indicators of alertness and performance.
The study, titled “Effects of 90- and 30-min naps or a 120-min nap on alertness and performance: reanalysis of an existing pilot study”, was published on 18 June 2023 in Scientific Reports and was funded by the Japan Society for the Promotion of Science.
Table of Contents
Frequently Asked Questions (FAQs) about night shift napping
What is the ideal nap strategy for night shift workers?
Recent studies suggest that taking two separate naps—a 90-minute session before midnight followed by a 30-minute session in the early hours—is more effective in combating drowsiness and fatigue than a single prolonged nap.
Who can benefit from these nap findings?
While the findings are primarily directed at night shift workers, especially in healthcare, they can also be invaluable to new parents, emphasizing the importance of nap timing and distribution.
How were the findings derived?
The conclusions were based on a detailed examination of pilot studies on night shift napping conducted from 2012 to 2018. These studies explored various nap routines and their impacts on fatigue and cognitive function.
What are the negative implications of a single prolonged nap?
Participants who took a single 120-minute nap experienced heightened drowsiness by 4 a.m., which persisted until the end of their shift.
How does nap timing affect its effectiveness?
The timing of the nap is crucial. Delaying it can combat fatigue more effectively, but excessive postponement might diminish concentration.
Are these findings applicable to other populations?
Yes, aside from night shift workers, the researcher, Sanae Oriyama, believes that these findings can assist new parents in managing sleep deprivation.
Was this research conducted in a controlled environment?
Yes, the research comprised of 41 female participants in their 20s who were invited to a controlled environment mimicking a 16-hour night shift. Various parameters, such as temperature, light, and sleep settings, were standardized, and participants were monitored for different indicators of alertness and performance.
More about night shift napping
- Scientific Reports Journal
- Effects of Napping on Alertness and Performance
- Hiroshima University’s Graduate School of Biomedical and Health Sciences
- Japan Society for the Promotion of Science
- The Impact of Night Shift Work on Health
- Uchida-Kraepelin Test Explained
6 comments
This could be a game changer for me. i work night shifts and always feel dead by 4am. thanks for sharing this. gonna tweak my nap schedule.
huh, never really though about nap timing that much. but it makes sense especially if you’re pulling an all-nighter. gotta try this out.
wow, that’s some interesting findings there! always thought a long nap was the way to go during my night shifts. maybe i need to change my routine a bit…
is it just me or does a 90 min nap sound a tad too long? I usually just go for a quick 20 min power nap and feel rejuvenated. but maybe I’m doing it wrong? not sure.
its fascinating how research always brings new insights. i always felt more refreshed after shorter naps but never knew there was science behind it.
so basically, two naps are better than one? i wish i’d known this when I was working those long hospital shifts back in the day.