Get a good night’s sleep before the big meeting, but better yet, get enough sleep every night, follow a routine, and don’t stay out late even if you can sleep in, according to an MIT study that furthers our understanding of the productivity benefits of sleep.
Many studies have confirmed the importance of sleep on our cognitive functions — our ability to think clearly and work productively. While previous studies use self-report surveys or a laboratory context to gather data, a new MIT study collected data on sleep and its benefits through fitbit devices worn throughout an entire semester by 88 students in a chemistry class. The fitbit objectively tracked the duration and quality of the students’ sleep each night. This data was then compared to results in the classroom, specifically the individual grades on 8 quizzes and three mid-term exams and an overall score for the class based on the sum of the quiz and exam grades.
An analysis of the collected data yielded both expected and unexpected results.
- The more participants slept (sleep duration), the higher their overall score for the class. In addition, the better participants slept as measured by the fitbit’s sleep quality metrics (based on variances in heart beat that indicate whether the sleep is in a light sleep, deep sleep or REM sleep), the higher they scored.
- The timing of sleep proved to have a significant impact on performance. The earlier participants went to bed, the higher their overall score. Likewise, the earlier participants woke up, the higher their overall score.
- Consistency — going to sleep and waking up at about the same time every night — was also a factor. The more inconsistently participants slept, the lower they scored.
Somewhat unexpectedly, the old adage about getting a good night’s sleep before the big day was proven wrong.
- In terms of both quality and duration, a long and/or good sleep the night before a quiz or one of the three mid-terms during the semester did not translate into higher scores for the participants.
- A full and/or good night’s sleep for a straight week before a quiz or a mid-term during the semester did translate into somewhat higher scores. For example, participants who slept for sufficient hours for a week before the 8 quizzes did significantly better on 3 of them and slightly better on another 3. The positive impact was less evident for participants who had high quality sleep for a week before the quizzes: they did significantly better on 1 of them and slightly better on another 3.
- The most significant result came from participants who slept long enough and well for a month before a quiz or a mid-term: They scored significantly higher on all the quizzes than those who had slept less or less well during the week or the night before.
The research also revealed some gender differences, perhaps explaining why, in the academic setting at least, women, in general, tend to outperform men.
- While the longer participants sleep the better the quality of their sleep, this was especially true for the male participants—indicating that it is more important for men to sleep longer if they want high-quality sleep.
- Consistency in their sleep hours was also more important for men. The research showed that men more than women slept better and performed better with consistent sleep. Thus, it is more important for men to stick to a regular sleep schedule in order to achieve high-quality sleep and perform well.
The negative impact of poor sleep on workplace productivity has been shown in previous studies. Although the context of this research is academic, the lessons drawn apply to your employees and your workplace:
- A good night of sleep before a big presentation, for example, is always a good idea; this sleep, however, won’t overcome the lower quality work that might have been caused by poor sleep in the days (or perhaps weeks) during which the presentation was created.
- Thus, planning and time management is key to productivity and work quality. Those who believe they “work better under pressure” are ignoring the proven cognitive damage of “cramming” to make a deadline.
- The research also highlights the importance of making sleep a habit. Consistent sleep hours over time lay the groundwork for high performance.
- Finally, it seems that men need better sleep than women—a fact that few of your male employees would ever consider.
In addition to increasing employee awareness and the willingness to acquire good sleep habits, organizations can take additional steps:
- With the blurring of work and home, it is easy for employees and managers to feel they must read and answer work emails before going to sleep, or even take work home with them. Encourage your people to rest off-work hours, even if they work from home.
- Avoid coerced overtime hours, because of unrealistic deadlines for deliverables, for example, or a culture that rewards long hours in the office.
In the long term, a rested, productive employee or manager is the best outcome for the individual and your organization.
FURTHER READING Kana Okanos profile at Massachusetts Institute of Technolog Jakub R. Kaczmarzyks profile at Massachusetts Institute of Technology John D. E. Gabrielis profile at Massachusetts Institute of Technology Jeffrey C. Grossmans profile at profile at Massachusetts Institute of Technology MIT Sloan School of Management Executive Education profile at IEDP
Sleep Quality, Duration, and Consistency Are Associated with Better Academic Performance in College Students. Kana Okano, Jakub R. Kaczmarzyk, Neha Dave, John D. E. Gabrieli & Jeffrey C. Grossman. npj Science of Learning (2019).