Be prepared: Does psychological reattachment buffer the effect of a bad night's sleep on day‐specific work engagement and proactivity?

Psychological reattachment means mentally tuning into one's work before starting work in the morning. In this daily diary study, we investigated whether psychological reattachment may be beneficial not only for work engagement but also for proactivity during the day. We moreover considered two competing theoretical propositions regarding the role of psychological reattachment in the effect of sleep quality on work engagement and proactivity. The first proposition assumes a cognitive, self-regulatory perspective in which psychological reattachment serves as a moderator, buffering the detrimental effect of poor sleep quality on work engagement and proactivity. The second proposition assumes an energetic process in which psychological reattachment may benefit from a good night's sleep and thus serve as a mediator for the beneficial effect of sleep quality on work engagement and proactivity. We conducted a daily diary study over ten consecutive workdays. Altogether, we collected data from 171 employees on 1186 days. The results indicated that on days with good sleep quality and higher psychological reattachment, work engagement and proactivity were higher. Day-specific psychological reattachment buffered the negative effects of a poor night's sleep on work engagement, supporting the first of our competing hypotheses. Finally, we present ideas on how to foster psychological reattachment in practice.