The effects of a 120-minute nap on sleepiness, fatigue, and performance during 16-hour night shifts: A pilot study

Abstract

Objective To investigate sleepiness, fatigue, and performance following a 120‐minute nap during simulated 16‐hour night shifts based on subjective and objective assessments. Methods Fourteen females participated in this crossover comparative study. Three experimental nap conditions were used: naps from 22:00 to 00:00 (22‐NAP), 00:00 to 02:00 (00‐NAP), and 02:00 to 04:00 (02‐NAP), respectively. Measurement items were sleep parameters, sublingual temperature, a Visual Analog Scale for sleepiness and fatigue, a single‐digit mental arithmetic task (for 10 minutes), and heart rate variability. Participants wore an ActiGraph to estimate their sleep state. Results There was no difference in the sleep parameters at the time of naps among the three conditions. Immediately following a 120‐minute nap, sleepiness and fatigue increased, and the number of calculations performed in the single‐digit mental arithmetic task decreased in any of the conditions. In particular, immediately after the 02‐NAP, fatigue and high‐frequency power (HF) were higher than after the 22‐NAP. In the early morning (from 05:00 to 09:00), in the 22‐NAP, sleepiness and fatigue increased, and performance and sublingual temperature decreased more than in the 00‐NAP and 02‐NAP. Furthermore, the ratio of errors was significantly lower in the 00‐NAP than in the 22‐NAP in the early morning. Conclusions A 120‐minute nap taken from 22:00 to 02:00 may cause temporary sleepiness after waking, increase fatigue and reduce performance. Greater attention should be given to naps taken at a later time (ie, 02‐NAP). In addition, taking a nap starting at 00:00 might decrease the risks of errors in the morning.

Guidelines for Reducing the Adverse Effects of Shift Work on Nursing Staff: A Systematic Review

“…Music therapy has proven particularly effective in supporting mental health and sleep among nurses with circadian rhythm sleep disorders. The retrospective study by Wang et al demonstrated that integrating music therapy with pharmacological treatment using melatonin receptor-2 agonists led to a significant improvement in sleep quality and a reduction in anxiety and depression symptoms, with an overall effectiveness rate of 85.56% compared to 50.56% in the control group [ 112 ].…”

Guidelines for Reducing the Adverse Effects of Shift Work on Nursing Staff: A Systematic Review

“…Music therapy has proven particularly effective in supporting mental health and sleep among nurses with circadian rhythm sleep disorders. The retrospective study by Wang et al demonstrated that integrating music therapy with pharmacological treatment using melatonin receptor-2 agonists led to a significant improvement in sleep quality and a reduction in anxiety and depression symptoms, with an overall effectiveness rate of 85.56% compared to 50.56% in the control group [ 112 ].…”

Physical and mental fatigue in shift work and mitigation strategies: an integrative review

“…These breaks help maintain aspects such as weight control, blood pressure, and circadian hormone balance. 19 , 23 - 25 For day shift workers, breaks can be taken between 1:00 p.m. and 5:00 p.m., 24 while, for professional drivers, 45 minutes of rest are needed after a maximum driving time of 4.5 hours. 26 …”

“…Taking naps during work breaks is highly recommended, especially for night shift workers and those who perform activities that require quick responses. 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

“… 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

Effects of shift work schedules, compensatory sleep, and work–family conflict on fatigue of shift‐working nurses in Chinese intensive care units

“…Although napping during the night shift improves psychomotor vigilance and performance, current evidence does not show an apparent reduction in fatigue. Nurses awakening from a night shift slumber may risk sleep inertia, which increases fatigue and reduces performance 53,54 . Future research should focus on the long‐term impact of napping during the night shift 27,55 .…”

Guidelines for Reducing the Adverse Effects of Shift Work on Nursing Staff: A Systematic Review

“…Music therapy has proven particularly effective in supporting mental health and sleep among nurses with circadian rhythm sleep disorders. The retrospective study by Wang et al demonstrated that integrating music therapy with pharmacological treatment using melatonin receptor-2 agonists led to a significant improvement in sleep quality and a reduction in anxiety and depression symptoms, with an overall effectiveness rate of 85.56% compared to 50.56% in the control group [ 112 ].…”

Physical and mental fatigue in shift work and mitigation strategies: an integrative review

“…These breaks help maintain aspects such as weight control, blood pressure, and circadian hormone balance. 19 , 23 - 25 For day shift workers, breaks can be taken between 1:00 p.m. and 5:00 p.m., 24 while, for professional drivers, 45 minutes of rest are needed after a maximum driving time of 4.5 hours. 26 …”

“…Taking naps during work breaks is highly recommended, especially for night shift workers and those who perform activities that require quick responses. 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

“… 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

Effects of shift work schedules, compensatory sleep, and work–family conflict on fatigue of shift‐working nurses in Chinese intensive care units

“…Although napping during the night shift improves psychomotor vigilance and performance, current evidence does not show an apparent reduction in fatigue. Nurses awakening from a night shift slumber may risk sleep inertia, which increases fatigue and reduces performance 53,54 . Future research should focus on the long‐term impact of napping during the night shift 27,55 .…”

Guidelines for Reducing the Adverse Effects of Shift Work on Nursing Staff: A Systematic Review

“…Music therapy has proven particularly effective in supporting mental health and sleep among nurses with circadian rhythm sleep disorders. The retrospective study by Wang et al demonstrated that integrating music therapy with pharmacological treatment using melatonin receptor-2 agonists led to a significant improvement in sleep quality and a reduction in anxiety and depression symptoms, with an overall effectiveness rate of 85.56% compared to 50.56% in the control group [ 112 ].…”

Physical and mental fatigue in shift work and mitigation strategies: an integrative review

“…These breaks help maintain aspects such as weight control, blood pressure, and circadian hormone balance. 19 , 23 - 25 For day shift workers, breaks can be taken between 1:00 p.m. and 5:00 p.m., 24 while, for professional drivers, 45 minutes of rest are needed after a maximum driving time of 4.5 hours. 26 …”

“…Taking naps during work breaks is highly recommended, especially for night shift workers and those who perform activities that require quick responses. 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

“… 19 , 23 - 25 However, in night shift workers, these naps should not exceed 120 minutes and should not occur before midnight, since they can increase fatigue due to the reduction in body temperature that occurs after long naps. 25 …”

Effects of shift work schedules, compensatory sleep, and work–family conflict on fatigue of shift‐working nurses in Chinese intensive care units

“…Although napping during the night shift improves psychomotor vigilance and performance, current evidence does not show an apparent reduction in fatigue. Nurses awakening from a night shift slumber may risk sleep inertia, which increases fatigue and reduces performance 53,54 . Future research should focus on the long‐term impact of napping during the night shift 27,55 .…”