We aimed to examine the effects of the daily rest period (DRP) on resting blood pressure (BP) and fatigue and determine the optimal DRP for daytime workers. Fifty-four daytime employees participated in a 1-month observational study. BP was measured thrice at the workplace. Employees underwent a pre- and post-survey to determine the usual DRP and assess subjective health outcomes. To determine the optimal DRP, DRP criteria were set as 11, 12, 13, and 14 hours. Workers with a shorter DRP had high diastolic BP and fatigue. Diastolic BP was higher in the short group than in the long group for the 14-hour DRP criteria alone. Shorter DRP was associated with high diastolic BP. We recommend a longer DRP (≥14 hours) for improving workers’ cardiovascular health.

Objectives: This study aimed to describe the sleep quantity, sleep quality, and daily rest periods (DRPs) of Japanese permanent daytime workers. Methods: Information about the usual DRP, sleep quantity, and sleep quality (Japanese version of the Pittsburgh Sleep Quality Index: PSQI-J) of 3,867 permanent daytime workers in Japan was gathered through an Internet-based survey. This information was analyzed and divided into the following eight DRP groups: <10, 10, 11, 12, 13, 14, 15, and ≥ 16 h. Results: The sleep durations for workers in the <10, 10, 11, 12, 13, 14, 15, and ≥ 16 h DRP groups were found to be 5.3, 5.9, 6.1, 6.3, 6.5, 6.7, 6.7, and 6.9 h, respectively. The trend analysis revealed a significant linear trend as the shorter the DRP, the shorter was the sleep duration. The PSQI-J scores for the <10, 10, 11, 12, 13, 14, 15, and ≥ 16 h DRP groups were 7.1, 6.7, 6.7, 6.3, 6.0 (5.999), 5.6, 5.2, and 5.2, respectively. The trend analysis revealed a significant linear trend as the shorter the DRP, the lower was the sleep quality. Conclusions: This study described sleep quantity, sleep quality, and DRP in Japanese daytime workers. It was found that a shorter DRP was associated with poorer sleep quantity as well as quality.

More knowledge is required to determine the optimal shiftwork schedule to reduce the harmful effects of short restart breaks between shifts. This 5-month intervention study aimed to examine the effectiveness of extended restart breaks from 31 h to 55 h after consecutive night shifts by considering the characteristics of the circadian rhythm to mitigate fatigue and sleep among 30 shift-working nurses. Subjective and objective variables, such as vital exhaustion, distress, hair cortisol, salivary C-reactive protein, and sleep mattress sensor sensation, were repeatedly measured to examine the differences between the intervention and control conditions. Two-way (condition × time) multilevel analyses showed significantly lower levels of vital exhaustion and distress in the intervention condition (p = 0.005 and p = 0.004, respectively). However, the expected benefit of the intervention was not observed in objectively measured variables. These findings suggested that an extended restart break after consecutive night shifts can moderately decrease occupational fatigue and stress.

Objectives This study examined the effects of work-related electronic communication (WREC) during non-working hours in the work from home or office setting on health. Methods The study recruited 98 information technology workers in a 9-day observational study. They recorded work–life events (eg, work style (working mostly from home or the office) and duration of WREC during non-working hours) and subjective ratings (eg, current fatigue, sleepiness and depression) and wore a sleep actigraph to measure objective sleep variables before bedtime every day. They completed the Brief Psychomotor Vigilance Test (PVT-B) before bedtime for 4 days. Results The frequency of WREC was significantly higher when working mostly from home than in the office (p<0.01). In addition, the duration of WREC was longer when working mostly from home than in the office (p<0.001). Linear or generalised linear mixed model analysis for fatigue, depression and PVT lapse revealed significant interaction effects between work style and WREC (all p<0.05). Post hoc analysis showed that the longer the WREC, the worse the fatigue and depression and the lower the lapse on working mostly from the office (all p<0.05). Conclusions Longer WREC is associated with worse fatigue and depression and lower lapse of PVT (higher alertness) before bedtime for working mostly from the office. Workers, especially those working from the office, should minimise WREC during non-working hours to maintain good health. Therefore, companies, managers and other relevant stakeholders should refrain from contacting workers during non-working hours.

A daily rest period (DRP) is a daily inter-work interval that contains sleep opportunity. This study investigates the joint association of DRP and sleep duration with worker health and productivity. A total of 13,306 Japanese daytime workers participated in this web-based cross-sectional survey. Participants reported on their DRPs and sleep duration; moreover, sleep difficulties, mental health, and presenteeism were assessed by the standardized questionnaires. The participants were divided into 10 groups based on their DRPs and sleep duration. Logistic regression analyses showed that the combination of quick return (QR: DRP of <11 h) and short sleep duration (<6 h) was found to be significantly associated with sleep difficulties (odds ratio [OR] = 4.45, 95% confidence interval [CI] = 2.83–7.01), poor mental health (OR = 3.04, 95% CI = 1.79–5.15), and presenteeism (OR = 2.35, 95% CI = 1.47–3.77) compared with the reference group (the combination of adequate DRP [15 h] and a normal sleep duration [≥6 h]). The combination of QR and normal sleep duration or adequate DRP and short sleep duration was significantly associated with high ORs for the outcomes. QR, short sleep duration, or both negatively affect worker health and productivity.

The aim of this study was to clarify the relationship between sleep disturbances and depression in daytime workers using a structured interview. A total of 1,184 daytime workers were enrolled. We evaluated difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), and global insomnia scores (ISs) in all participants. As a result, the prevalences of DIS, DMS, and EMA were 16%, 46%, and 22 %, respectively. IS was significantly correlated with depression score. Additionally, although all IS subscales (i.e., DIS, DMS, and EMA) were significantly associated with depression score, the main factor contributing to depression score was DIS. Thus, the present study reveals that sleep disturbances and especially DIS are associated with depression in daytime workers.