Nurses have a vital function within the healthcare system, being the largest human resource in the care team [1]. They face various challenges in their work environment, such as work-related stress, fatigue, difficult relationships, occupational hazards, heavy workload, job satisfaction, and stressful conditions [1,2]. These factors can negatively impact their professional performance and lead to stress-related illnesses, burnout, and even leaving their jobs, ultimately affecting their quality of life [3,4]. Moreover, working in stressful environments can result in high turnover rates, imposing significant costs on the healthcare system [5]. Prioritizing the physical and mental health of nurses is crucial, as it has a direct correlation with the quality of patient care. This is especially evident during global health emergencies, such as the COVID-19 pandemic, where nurses face significant challenges. Therefore, it is imperative to provide comprehensive support to nurses in every facet of their lives [6,7].

It has been demonstrated that nurses belong to a professional cohort that frequently experiences depression and stress [2,3,5]. Furthermore, there is substantial evidence indicating that nurses encounter significant levels of stress and pressure within their work settings, which can have a detrimental impact on their emotional well-being, potentially leading to depression [4-6]. Research conducted in China involving 52,592 participants revealed that 43.83% of nurses exhibited depressive symptoms [2]. Depression and stress have detrimental effects not only on the well-being of nurses but also on the workforce and the quality of healthcare [8-10]. These effects include attrition from the workforce, an increase in medical errors, and a decrease in patient satisfaction. The adverse impact of psychological distress on the health and productivity of nurses necessitates a thorough investigation into potential solutions and strategies aimed at enhancing their mental well-being, particularly concerning issues such as depression and stress. Engagement in physical activity (PA) is one of the factors that may help alleviate depression and stress, thereby enhancing individuals’ mental well-being.

Engaging in PA is a strategy that individuals employ to promote mental health [11,12]. PA not only benefits physical health but also plays a significant role in enhancing mental well-being [11,13]. Furthermore, it fosters the development of talents and contributes to the improvement of self-confidence, self-esteem, social acceptance, and social compatibility [14]. Ultimately, participating in PA enables individuals to overcome various physical, mental, and psychological challenges within work settings [13,15,16]. The various advantages associated with engaging in PA for both physical and mental health, as previously noted, suggest that incorporating PA can serve as a viable approach to enhancing the psychological well-being of nurses, particularly in relation to issues such as depression and stress. In addition, the World Health Organization (WHO) advises adults to participate in 150 minutes of moderate PA (MPA) per week, 75 minutes of vigorous PA (VPA) activity per week, a combination of both, or achieve 10,000 steps per day [17]. Nurses frequently find themselves walking or standing due to the demands of their job, although this can vary depending on their shift schedule [18]. Research indicates that despite the active nature of the nursing work environment, nurses engage in minimal PA outside of work and fail to meet the WHO’s recommended guidelines for health-oriented PA (i.e., moderate-to-vigorous PA) [19-22]. This lack of PA contributes to the high prevalence of obesity and overweight among nurses [23,24]. Given the known benefits of participating in health-oriented PA on mental health [11,12,14], this study aimed to investigate whether PA could impact depression and stress levels, which are crucial indicators of mental health, in nurses.

Moreover, resilience is an essential element that can affect the mental wellness of a person [25]. Resilience is considered one of the most vital abilities possessed by humans, as it enables them to effectively adapt to stressors and psychological pressures in challenging circumstances [26,27]. The concept of resilience refers to the process, ability, or consequence of effectively adjusting to threatening environmental conditions, playing a significant role in coping with life-threatening situations [27]. Resilient individuals exhibit heightened self-confidence and competence when confronted with unpredictable and stressful conditions [25]. Research has demonstrated that people who possess strong resilience are more inclined to preserve their mental well-being and experience greater psychological adjustment during stressful and unfortunate situations [27-30]. Moreover, studies have shown that enhancing resilience not only improves mental health but also enhances job satisfaction [31]. In the healthcare field, resilience among personnel leads to increased flexibility, resulting in better patient care and self-care practices [26-28]. As previously discussed, resilience has beneficial impacts on various psychological aspects. Additionally, it plays a significant role in enhancing the capacity to endure the challenges associated with the nursing profession, which is particularly demanding. Therefore, it is reasonable to regard resilience as a crucial factor in promoting the psychological well-being of nurses, particularly in relation to issues such as depression and stress. In addition, the significant demand for nurses has underscored the necessity of cultivating a strong and adaptable workforce. Consequently, it is plausible to suggest that the mental health of nurses may be affected by their resilience. Within this study, resilience is regarded as a mediator in the correlation between PA with depression and stress in nurses. Consequently, the second objective of this research was to examine the mediating function of resilience in the correlation between PA with depression and stress among nurses.

Given the challenging working conditions faced by nurses, which can lead to mental health issues such as depression and stress, it is essential to prioritize their physical and mental well-being. Comprehensive support for nurses in all aspects of their lives is crucial. This situation calls for an in-depth exploration of potential solutions and strategies aimed at improving their mental health, particularly in relation to depression and stress. Furthermore, considering the numerous benefits of PA for both physical and mental health, along with the positive effects of resilience on various psychological dimensions and work performance, this study aims to examine the structural relationships between PA and resilience in relation to depression and stress among nurses. In total, the aim of current research was to explore the correlation between PA with depression and stress among nurses, with a focus on the mediating role of resilience. The practical purpose of this research was to clarify the connections among PA, resilience, and mental well-being in the nursing profession. By evaluating levels of PA and resilience, it may be possible to customize interventions that target particular elements contributing to mental well-being among nurses, thereby enhancing the efficacy of strategies designed for symptom management.

Due to the hard-working conditions, nurses face depression and stress [2,5,6]. On the other hand, PA is considered an effective and important factor in improving mental health [11-13]. Therefore, the purpose of current research was to explore the correlation between PA with depression and stress among nurses, with a focus on the mediating role of resilience. Initially, it is important to note that the findings revealed that the nurses involved in this research exhibit a moderate level of depression and stress. Furthermore, it was observed that women experience higher levels of depression compared to men. These findings align with the results of Chidiebere Okechukwu et al. [7], Babapour et al. [8], Zakeri et al. [9], and Chen and Meier [10], and suggest that working as a nurse can potentially result in psychological issues such as depression and stress. Moreover, the influence of biological factors, including genetic and hormonal influences, alongside psychological aspects such as the tendency to employ emotion-focused coping strategies in response to stress, and sociological elements like the nature of trauma experienced, suggests that the effects are more significant for women compared to men. Although additional research is required to identify the underlying cause of this gender disparity among nurses, these results highlight the unique challenges and pressures faced by female nurses in their work environment. Future research endeavors should prioritize exploring interventions aimed at enhancing the mental well-being of nurses, particularly focusing on women.

Moreover, the findings regarding the pattern of PA are interesting. Upon calculating the ratio of step counts to working hours, it was observed that the average step counts were higher in day vs. night shift, with no significant difference between weekdays and weekend days. Upon further examination of daily step counts, it was determined that participants averaged 8,739.56 steps per day, which are in line with the findings of Chang and Cho [19], Fijačko et al. [20], Chappel et al. [21,22], falls short of the WHO’s recommended daily target of 10,000 steps. Nevertheless, the correlation test results indicated that the step counts do not notably enhance mental health indicators such as depression and stress. These outcomes suggest that PA nurses undertake during work may not be health-focused activities and may not contribute to improving mental health. Hence, the primary emphasis should likely be on nurses’ PA outside of the working hours.

In addition, it was found that the nurses involved in the research had an average of 120.51 minutes of MPA and an average of 25.91 minutes of VPA per week, which are in line with the findings of Chang and Cho [19], Fijačko et al. [20], Chappel et al. [21,22], indicating lower levels of MPA and VPA among nurses. Furthermore, when considering gender differences, the study revealed that men were engaging in significantly higher levels of MPA and VPA compared to women. This information highlights the importance of addressing gender disparities in PA levels. Moreover, the study also found that engaging in health-oriented PA, such as MPA and VPA, could potentially help alleviate depression and stress among nurses. Despite not meeting the recommended guidelines set by the WHO, higher levels of MPA and VPA were significantly associated with lower levels of depression and stress. These findings align with Zou et al. [35], Bischoff et al. [36], Lautenschlager [37], and BidzanWiącek et al. [38] and demonstrate the beneficial impact of engaging in health-focused PA on mental well-being, including depression and stress. Clinical studies have put forth various mechanisms to explain the positive impact of PA on depression and stress. These mechanisms include the increased production of serotonin, dopamine, and norepinephrine, which are commonly known as “feel-good” hormones. These hormones are essential for reducing stress and enhancing overall well-being [39].

Based on our findings, which indicate that the step counts do not impact depression and stress levels, it is recommended that nurses prioritize engaging in MPA and VPA outside of their work environment. This will allow them to reap the numerous health benefits associated with PA. Given the demanding nature of nurses’ jobs, including rotating night and day shifts throughout the week and month, and recognizing the crucial role of nurses’ physical and mental well-being in ensuring the optimal efficiency of the healthcare system, health officials should meticulously and comprehensively devise plans to enhance the participate of nurses in health-oriented PA that promote their overall health and well-being.

In relation to PA patterns, it is important to highlight that sedentary behavior demonstrated a direct and significant correlation with depression and stress. Sedentary refers to any waking activity that is performed while sitting or lying down [40]. Given that nurses primarily engage in sitting or standing during work, it is expected that they spend a significant amount of time being sedentary. Our findings also indicate that approximately 65% of the nurses’ total accelerometer time is attributed to sedentary behavior. Consequently, based on these findings, which are in line with the findings of Chang and Cho [19], Fijačko et al. [20], Chappel et al. [21,22], it can be anticipated that nurses have a relatively high level of sedentary time, which can lead to various physical and mental health issues in the future due to the detrimental effects of sedentary behavior. Furthermore, our results demonstrate that the participants experience depression and stress, which could be attributed to their prolonged periods of being inactive. Additionally, considering that female nurses had higher sedentary time compared to males, it can be inferred that the elevated levels of depression, stress, and BMI among female nurses may be influenced by their increased sedentary behavior.

Finally, our findings demonstrated that resilience has a mediating function in the correlation between PA pattern (comprising step counts, sedentary time, LPA, MPA, and VPA) with depression and stress among nurses. To the best of our knowledge, there is no single study that examined this issue, however, these findings hold significant importance as they demonstrate the favorable impact of both resilience and PA on the mental well-being of nurses, specifically in terms of depression and stress. To interpret these findings, it can be stated that enhancing resilience fosters improved coping mechanisms and defense strategies in individuals [26,27]. Nurses with strong resilience are possibly able to utilize positive adaptive skills to effectively manage stress and thrive in the demanding hospital environment [25]. The greater a person’s resilience and ability to handle life’s challenges and pressures, the lower their susceptibility to mental and emotional disturbances [27,29]. Those with high resilience are possibly able to preserve their psychological health during times of stress and adversity, demonstrating psychological flexibility. Resilience plays a crucial role in adaptation, life satisfaction, and mental health [25]. By influencing an individual’s emotions and feelings, resilience promotes a positive outlook and ultimately, life satisfaction. Individuals with high resilience assess stressful situations and then employ rational solutions to steer these circumstances in a desired direction. Such individuals experience contentment, self-assurance, and self-belief in challenging conditions [29,30].

This study had several strengths. For instance, the utilization of accelerometer tools for tracking PA allowed for a relatively accurate assessment of nurses’ PA pattern, including step counts and time. Furthermore, the research effectively examined PA levels during shifts and outside of working hours, enabling the identification of a relatively comprehensive pattern for PA behaviors of nurses. However, there were limitations to the study. The research did not specify the types of activities nurses engaged in outside of working hours, such as aerobic or anaerobic exercises, or specific sports like yoga. Future studies should address this gap by focusing on the types of activities nurses participate in and exploring the impact of intervention programs targeting various PAs on mental health. Additionally, we did not measure the nurse-to-patient ratio during shifts, which could influence the results. Future research should account for this factor and its potential effects on outcomes. Lastly, the inability of accelerometers to track aquatic activities means that water sports like swimming during off-shift hours were not included in the study. Therefore, future research should investigate the types of PAs, including aquatic activities, nurses engage in outside of work hours.