This study investigated nurses’ physical demands at work using both objective and subjective measurement methods. Nurses ‘number of steps and distance traveled on each shift were measured objectively using an activity tracker, and the subjective perceptions of nurses’ physical demands for each shift were surveyed through questionnaires. Measurements of the number of steps and the distance traveled for three shifts were made for all nurses who participated in this study. Accordingly, it was possible to include data from the evening shift in the comparative analysis in this study, unlike previous studies [4, 16, 17]. In order to overcome the limitations of a previous study that used a pedometer physical activity was measured using a reliable smart band  that was light enough for nurses to wear while working.
The average number of steps that nurses walked while working an average of 9.4 h per shift was 9360 steps, and the distance traveled was 5.79 km, which is consistent with the results of a study  that measured the number of steps and walking distance for nurses. The previous study suggested that the nurses’ workflow was related to their workload and found significant differences between day and night shifts and depending on the number of patients nurses were responsible for . Another previous study measured the walking distance of nurses during 10 h of work and showed a shorter measured value than the walking distance measured in this study . However, the present study is consistent with earlier research in that it found a longer walking distance on the day shift than on the night shift [4, 7, 16]. In a previous study that measured physical activity in the general public, the average number of steps per day was 8385 steps for women in general and 8875 steps for women aged 20 to 39 . In another similar study, an average of 7,500 to 9999 steps per day was classified as somewhat active, 10,000 to 12,499 steps as active, and 12,500 or more steps as very active; in that study, the average number of steps for women per day was 6486 indicating that the average physical activity of nurses was higher compared to the general population.
This study found that nurses worked long hours on night shifts and walked more than 8000 steps. The number of steps and the distance traveled during the night shift were lower than those of the day and evening shifts despite the significantly longer working hours. A previous study found that the average number of steps that nurses walked during the night shift was about 4000, whereas the number of steps during the day was more than 8000 . In comparison, the number of steps walked during the night shift in this study was substantially higher. Even when compared with a study of shift workers in other occupations , nurses’ physical activity during the night shift was found to be higher. A comprehensive comparison of the results of the present study to those of previous studies [16, 33] showed that nurses’ night shifts required considerable physical activity, as perceived by nurses themselves.
In this study, the highest number of steps was found for the day shift, followed in descending order by the evening and night shifts. In general, since treatment and surgery are performed during the daytime, it can be expected that nurses will be more physically active. However, these results were not consistent for all nursing units. Unlike other nursing units, the emergency room had the highest number of steps on the evening shift, followed in descending order by the day and night shifts, and by the night and day shifts for distance traveled. The emergency room involves a substantial amount of unpredictable work rather than routine work; therefore, it is reasonable to assume that nurses’ physical workload will increase when unpredictable patients more frequently visit the emergency room. Of note, while both the number of steps and distance traveled were higher on the evening shift, contradictory trends were found between the day and night shifts for these parameters, which means that a high number of steps do not always correspond to a long distance. Depending on the details of the job, nurses may have to take many steps in a narrow space, or they may have to walk a long distance to carry out their tasks with a wider stride. To further clarify the difference between the number of steps and the distance traveled, further research should investigate the association between nurses’ specific work tasks and physical activity.
The objectively measured results for the number of steps and distance traveled using an activity tracker showed the same pattern as the physical activity scores perceived by nurses. When the score for physical activity during the day shift was set to 100 points and nurses were asked to score the physical activity of the other shifts relative to the day shift, the scores for the evening and night shifts were 96.75 and 90.09 points, respectively. The corresponding ratios using the actual measured number of steps were 99.35 for the evening shift and 87.65 for the night shift, showing close alignment between the subjective and objective measurements. A previous study that measured and compared the physical activity of nurses with objective and subjective indicators found that while nurses overestimated their walking time, their standing time was underestimated . It was reported that the time nurses worked while standing was about four times higher than the time that they actually walked, and that when providing nursing care beside of the patients, they were more likely to perceive themselves as walking even when they were only taking a few steps while standing . Even considering that nurses are likely to confuse walking with standing during work, it is nonetheless clear that nurses’ subjective perceptions of their physical activity during work are relatively accurate.
In the present study, the emergency room had the highest number of steps and distance traveled compared to other nursing units, followed by the intensive care unit. These units had significantly higher values than were measured in the general ward. Although it might be reasonable to predict that nurses in general wards, who care for more patients and are required to move throughout a larger area, the present study instead found that nurses in special care units with a limited space walked much more than those in the general wards. Because nurses’ jobs require a variety of physical activities that depend on the occupational setting , it is necessary to investigate and compare the types and intensities of physical activities to reveal differences in physical activity and nursing performance according to nursing department and nursing content. However, this study only investigated and compared the physical activities required in general. Therefore, additional research is needed for a more specific analysis of physical activities in specialized wards such as emergency rooms and intensive care units.
In addition, it was found that the number of steps and distance traveled was higher among younger nurses and those with less work experience. The average number of steps for nurses with less than one year of unit experience was 11,000 or more, whereas it was only about 7000 steps for those with three years or more of experience, meaning that the least experienced nurses walked about 40% more than nurses with three or more years of experience. This discrepancy can be accounted for by differences in competency and roles according to career years. For example, nurses with less than one year of experience are more likely to spend more time in direct nursing care than nurses with longer experience, and may need to walk back and forth between the nursing station and patient rooms more frequently if they miss necessary items due to a lack of experience. Multiple regression analysis in the present study also confirmed that the number of steps and distance traveled were significantly higher in the emergency room and intensive care unit than in the medical ward on all three shifts, as well as in nurses with shorter unit experience. In the comparative analysis between groups, participants with a higher education level showed significantly higher number of steps and distance traveled. However, in the multiple regression analysis, the education level did not significantly affect nurses’ steps and distance traveled. Collectively, these findings indicate that nurses’ physical activity, such as the number of steps and distance traveled, is most directly affected by the specificity of the nursing unit and the nurse’s unit experience.
Previous studies have examined the relationships between nurses’ job demands and health [2, 8, 10, 11, 13, 14, 34, 35]. Consistent reports from around the world have found that nurses suffer from musculoskeletal problems related to nursing work [5, 8, 19, 34, 36]. Since musculoskeletal problems are particularly likely to be linked to physical activity, it is necessary to conduct further analyses according to the characteristics and intensity of various physical activities during nurses’ work. A detailed list of physical activities should be compared with consideration of the nursing unit, nursing content, and individual characteristics in order to predict and manage the health risks related to physical activity. Scales such as the Therapeutic Intervention Scoring System (TISS-28 Scale) and Nursing Activity Score (NAS) have been developed to measure nurses’ activities, mainly by quantifying nursing intensity from the patient’s side . Accordingly, those scales have limitations insofar as they can only measure major nursing activities related to the patient’s condition. Therefore, through development of a scale that can comprehensively measure nurses’ actual work activities, physical demands and consequent physical and mental fatigue would enable a more accurate analysis. For example, a time-motion study could inform the development of a scale that would measure the time taken according to a list of all nurses’ activities and score them by applying the intensity according to the patient’s condition. Such a scale could be used to measure activity and fatigue for individual nurses, thereby providing data to understand the health status of nurses and manage their health. Through such initiatives, it would be possible to develop a health management program to reduce accumulated fatigue in body parts that are frequently used at work. This information could also be used for nursing managers to designate a working pattern or shift type suitable for nurses according to their health conditions and to supplement human resources in advance or to allocate them efficiently in the field.
There are several limitations of this study. First, although seven male nurses were included in the study, gender-related differences were not included in the analysis. Second, cautious interpretation is needed for the results of this study because the nurses who participated in the study were relatively young and the survey period was short. Third, this study was conducted at two tertiary hospitals, limiting the generalizability of the results. Because tertiary hospitals are substantially different from other hospital types in the number of beds, staff, facility size, and patient severity, further research is needed that would compare nurses’ physical demands according to the hospital category. Furthermore, even in the same nursing unit, there may be differences in nurses’ number of steps depending on the size of the unit and the number of nursing staff (Additional file 2). The results of this study should be interpreted with caution because all these points were not considered in detail and the classification was made according to the nursing unit. Fourth, although the smart band used in this study was easy to wear and light enough not to influence nurses ‘ability to move, there is a possibility that wearing an activity tracker might affect nurses’ intention to walk more, thereby leading to measurements that suggest inaccurately intense physical demands in some areas. Fifth, because nurses from various nursing units participated, the number of participants in each group may not be sufficient to compare the results of nurse groups between units. In order to analyze differences between units in the future, additional studies with more subjects are required.