Alternative model.

High levels of job demands are considered as the main predictor for teachers’ exhaustion, but longitudinal studies of the causal effects are few. Recently it has been suggested that research should further explore possible reciprocal relationships between stressors and strain and investigate if work rumination contributes to explain these relationships. In a sample of teachers (n = 1067) using a three-wave design, we hypothesized positive causal effects of job demands (work pace and role conflict) on affective work rumination, and of affective work rumination on exhaustion. We also hypothesized a positive reversed causal effect of exhaustion on affective work rumination, and of affective work rumination on job demands. Furthermore, affective work rumination was expected to mediate the positive causal and reversed causal effects between job demands and exhaustion. The results partly confirmed the expected causal and reversed causal effects. However, affective work rumination was only found to mediate the reversed causal effect of exhaustion and role conflict. Furthermore, a reciprocal relationship was only found between role conflict and exhaustion. The empirical, theoretical, and practical implications of the study are discussed.