Gaby
The strategy for staying alert during night shifts originated in Japan, a country known for its dedicated workaholics. Professor Sanae Oriyama from Hiroshima University proposed a method for effectively distributing short sleep periods during nighttime work to maintain energy levels. These recommendations could also be beneficial for new parents who find themselves awake at night.
The researcher evaluated the benefits of 30-minute, 90-minute, and 120-minute sleep intervals during a 16-hour night shift. She concluded that combining two shorter sleep periods—90 minutes and 30 minutes—was the most effective way to stay alert and reduce fatigue. In contrast, the 120-minute sleep proved to be the least effective in combating drowsiness.
The study involved 41 volunteers. Fifteen participants did not sleep at all during the simulated shift, 14 slept for 120 minutes, and 12 took naps of 90 and 30 minutes during the shift.
During the experiments, volunteers were asked to perform various tasks every hour. Researchers also requested participants to assess their fatigue levels. Those who napped only once during the night felt drowsy around 4:00 AM, while those who slept during two intervals experienced drowsiness at 6:00 AM.
Interestingly, participants from all groups reported feeling drowsy from 4:00 AM to 9:00 AM. However, for those who napped twice during their shift, the drowsiness was less intense.
Everyone knows that staying awake at night is detrimental to health. However, not everyone can avoid it, especially due to the nature of their work, such as emergency medical staff. In Japan, nurses are typically allowed to sleep for up to two hours during a 16-hour night shift. Nevertheless, Sanae Oriyama’s formula can also be applied by workers in other fields and by mothers who are sleepless due to their infants.
The findings of the study were published in the journal Science Advances.
