**1. Introduction**

Correction workers work under psychologically and physically demanding conditions [1–3]. They are frequently exposed to unexpected hold-over shift work that may result in circadian disruption, sleep loss, and increased fatigue. Also, correction workers experience constant threat of inmate assaults and riots, which can be emotionally draining due to hyper-alertness and anxiety [4]. Moreover, working conditions in the correctional setting are known to be associated with numerous types of health and performance outcomes, including immediate outcomes, like exhaustion and psychological distress, as well as more distant outcomes, like job dissatisfaction and impaired work ability [5]. According to the U.S. Department of Justice, correction workers, including correctional officers and administrative and support staff, are at higher risk of suicide, substance abuse, and divorce, while their mortality rate is the second highest of any occupation [6]. High turnover rates have also been reported [7].

The negative impact of demanding correctional work on correction workers' wellbeing can be explained by the classic stress-burnout model [8,9]. Adverse working conditions of correctional work act as stressors causing stress. These stressors lead to psychophysical strain symptoms, such as various forms of psychophysical burnout. Echoing this, empirical studies on correction workers have shown significant relationships between overwork and stress [8,10]. Also, studies have revealed that correction workers' stress is associated with burnout [8,11] and somatic symptoms [7].

These phenomena can also be understood within theoretical frameworks of the Job Demands-Resources model [12]. Exposure to the physically and psychologically demanding correctional working conditions with a lack of adequate resources is likely to deplete correction workers' psychological resources for socially adaptive and physically healthy self-regulatory behaviors [13]. Thus, correction workers' demanding work conditions can lead to exhaustion, which may then negatively influence healthy behaviors as well as socially adaptive behaviors. Additionally, Wright and Cropanzano showed that emotional aspects of exhaustion, which can be manifested in different forms, such as depression and stress, can undermine job performance [14].

In general, the negative impacts of demanding work conditions and subsequent psychophysical strain can be both extensive and derivative. Recent studies have shown various complications of stress. For example, stress can contribute to increased risk of cardiovascular diseases [15], while burnout, as an outcome of extended exposure to stress, can be associated with impairment of psychological resources, such as emotional intelligence and self-efficacy, as well as loss of social support [16]. Moreover, it was shown that burnout can negatively affect well-being at work, resources for coping, ability to work, and engagement [17]. Considering these findings, it can be inferred that specific adverse effects on workers' health in general (e.g., illnesses, psychological problems, obesity, etc.) are further compounded by compromised family health (e.g., marriage dysfunction, problematic children's behavior) and employer dissatisfaction (e.g., due to declined performance, increased health care costs). In corrections, work-related stress can lead to increased absentee rates, internal conflict, and suboptimal employee performance [18], all which may have reciprocal adverse influences on the work environment.

Our study attempts to elaborate the Job Demand-Resource model, which primarily focuses on stressors' impact on stress outcomes (strains), by examining the interrelations among the potential stress outcomes that are typical for correction workers. Our view is that the various stress outcomes do not simply occur in parallel, but instead are able to have synergistic effects when they occur in combination, in line with the view that stressor-strain relationships can be reciprocal [19,20]. Chronic exposure to the occupational context of correctional facilities, with its high demand that also lacks control or support, is likely to lead to various psychosocial and behavioral stress outcomes. In fact, Tennant found that enduring structural occupational stress can contribute to psychological disorders, like depression [21]. When confronted with different types of strain symptoms, one's resources, which are always limited in the case of correction workers, need to be used to cope with the extant symptoms first, whilst one's resources may not be adequately restored in a timely manner in order to respond to the emergence of additional strain symptoms. Subsequently, one's strain symptoms are likely to be exacerbated as more problems arise and as resources become more and more depleted.

The process of resource depletion is particularly concerning in situations in which strain symptoms are not simply end products but operate as derivative or secondary demands (or stressors). As various strain symptoms negatively affect a person in different ways when they are either within or outside the workplace, this suggests a person needs resources, including increased control and support, both within and outside the workplace to handle multiple strain symptoms. This inference aligns with the perspectives of Spillover Theory [22], as well as Conservation of Resources Theory [23]. Furthermore, when there is a lack of adequate resources, the stress-burnout process would accelerate because of the synergistic impact of multiple strain symptoms on resource depletion.

Our study explores the possible derivative or secondary role of strain symptoms as additional stressors. By doing so, the domains of stress intervention are also broadened from focusing exclusively on traditional stressors to also include strain symptoms themselves. This approach is not unlike secondary (i.e., reducing the impact of an injury and disease that has already occurred) or even tertiary (i.e., mitigating the impact of an ongoing injury and illness which has lasting effect) intervention approaches found in medical science and public health [24]. The dire implications of doing nothing

to prevent any worsening or exacerbation of the health situation for correction workers was also a motivating factor.
