The objective of this study was to analyze the influence of a 120-minute nap on daytime sleep and physical activity in nurses who worked 16-hour night shifts. To accomplish this, we measured the amount of physical activity for different nap groups. The subjects were 10 females (mean age, 21.5 years; standard deviation, 0.71). Three nap groups were established for separate nights during 16-hour night shifts: those taking a nap from 22:00-00:00 (22:00 nap), 00:00-02:00 (00:00 nap) or 02:00-04:00 (02:00 nap). The subjects were fitted with actigraphs, and their average amount of physical activity during the day (steps/min) and the quality of their nap and main sleep were measured. The 22:00 nap group had a longer nap time than 00:00 and 02:00 nap groups. Although the 22:00 nap group had a shorter total main sleep time, sleep efficiency was better. Moreover, fatigue in the 02:00 nap group decreased after the nap, and subjects in the 02:00 nap group had higher average levels of physical activity than the 22:00 nap group. These results suggest that a 120-minute nap starting at 02:00 is the most appropriate for individuals wanting to undertake physical activity after completing a 16-hour shift.
This study was conducted to identify the workload of disaster emergency response and the relationship between stress-related factors and mental health conditions among local govern ment employees one year after the 2011 Great East Japan Earthquake. A cross-sectional ques tionnaire study of 6,073 employees from 34 local government unit associations in Iwate, Miyagi and Fukushima Prefectures was undertaken from April to May 2012. The workload of disaster emergency response decreased gradually during one year after the disaster. About 20 percent of the participants showed a high degree of the psychological distress scale. The stressors, living conditions, disaster emergency response work, occupational she werealth and safety sys tem, critical incidence stress and emotional labour, were significantly associated to the stress response outcome. Assessing mental health conditions regularly and building a mental health support system for a long term after the disaster may be needed for the local government em ployees in the disaster-stricken area.