Background: High job demands and low job resources may cause job strain and eventually result in burnout. However, previous research has generally ignored the roles of time and self-regulation. Objectives: This theoretical article synthesizes the literature to propose a multilevel model that delineates how acute job strain translates into enduring and severe job burnout. Methods: We integrate self-regulation perspectives in job demandsresources (JD-R) theory to propose that short-term job strain and eventually enduring burnout is the result of consistently high job demands and low job resourcescombined with failed self-regulation. Results: The model shows that when employees are confronted with increased job strain, they are more likely to use maladaptive selfregulation strategies, such as coping inflexibility and self-undermining. In addition, when job strain increases, employees are less likely to use adaptive self-regulation strategies, such as job stress recovery and job crafting. It follows that when the job becomes more stressful, stable resources become more important. Organizational resources such as human resource practices and healthy leadership may help employees to regulate their short-term fatigue and avoid enduring burnout. Furthermore, key personal resources like emotional intelligence and proactive personality may help employees to recognize and regulate their fatigue in an effective way. Conclusion: The proposed model of burnout expands JD-R theory and offers important practical implications for the prevention and reduction of burnout.

This extensive overview of potential factors can inform intervention developers and implementers on which factors may play a role when introducing PA interventions in PHC. Future research should further investigate relationships between factors and PA promotion, which should be guided by qualitative in-depth knowledge on influencing factors.

Objective: Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. Methods: A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). Results: In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. Conclusions: This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout.

Exercise to reduce work-related fatigue among employees: a randomized controlled trial by de Vries JD, van Hooff MLM, Geurts SAE, Kompier MAJ This study shows that exercise has the potential to serve as a relatively simple and inexpensive secondary prevention strategy to improve (long-term) well-being among employees experiencing high work-related fatigue. The extent to which the exercise intervention under study caused beneficial effects in work-related fatigue depended on participants' compliance, underlining the challenge of implementing exercise interventions in practice among fatigued employees. Affiliation 337Original article Scand J Work Environ Health. 2017;43(4):337-349. doi:10.5271/sjweh.3634 Exercise to reduce work-related fatigue among employees: a randomized controlled trial Objectives The present study evaluated the efficacy of an exercise intervention to reduce work-related fatigue (emotional exhaustion, overall fatigue, and need for recovery). The effects of exercise on self-efficacy, sleep, work ability, cognitive functioning and aerobic fitness (secondary outcomes) were also investigated.Methods Employees with high levels of work-related fatigue were randomly assigned to either a 6-week exercise intervention (EI; N=49) or a wait-list control group (WLC; N=47). All participants were measured pre-(T0) and post-intervention (T1). EI participants were also measured 6 (T2) and 12 weeks (T3) after the end of the intervention. Analyses were based on intention-to-treat (ITT) and per-protocol (PP). PP analyses only included EI participants (N=31) who completed the intervention and WLC participants (N= 35) who did not increase their exercise level during the wait period.Results Analyses of covariance (ANCOVA) revealed that, at T1, the EI group reported lower emotional exhaustion and overall fatigue than the WLC group, however, only according to PP analyses. Both according to ITT and PP analyses, EI participants showed higher sleep quality, work ability, and self-reported cognitive functioning at T1 compared to WLC participants. Intervention effects were maintained at T2 and T3. ConclusionsThe exercise intervention had enduring effects on work-related fatigue and broader indicators of employee well-being. This study demonstrates that, in case of work-related fatigue, exercise does constitute a powerful medicine for those who comply with the treatment.