Stress beliefs shape daily affective reactivity to social and work stressors: A 7-day ecological momentary assessment study.

Stress beliefs-general expectations about the nature and consequences of stress-have been linked to health and performance, yet their role in shaping responses to everyday stress remains less understood. This study examined whether stress beliefs moderate affective reactivity and stress regulation strategies in response to naturally occurring stressors in daily life. In a 7-day ecological momentary assessment study, 104 university students completed thrice-daily reports (1,939 observations) on social and work-related stressors, positive and negative affect, and two stress regulation strategies-situation selection and response modification-as proposed in the stress optimization model (Crum et al., 2020). At baseline, stress beliefs were assessed alongside variables to characterize the sample. Negative stress beliefs moderated the association between daily stressors and positive affect: Individuals with high negative stress beliefs showed reduced positive affect during social stress and no increase in positive affect under higher workload. By contrast, those with low or moderate negative stress beliefs maintained positive affect during social stress and showed increased positive affect under higher workload-consistent with a challengelike appraisal. Additionally, controllability beliefs buffered increases in negative affect in response to daily social stress, with lower beliefs linked to stronger affective reactivity. By contrast, stress beliefs did not moderate associations between daily stressors and the investigated stress regulation strategies. These findings suggest that stress beliefs tune affective reactivity to everyday social and work stressors, identifying them as a potential intervention target given the established links between affect and long-term health. The generalizability of these findings should be confirmed across broader populations. (PsycInfo Database Record (c) 2026 APA, all rights reserved).