Leader Extraversion as a Boundary Condition in the Relationship between Transformational Leadership, Vitality, and Job Improvement.

We examine the relationship between transformational leadership and job improvement behaviors by considering the moderating effect of leader extraversion and the mediating role of employee vitality. Multi-level path analysis on data from 101 leaders and 619 subordinates provided support to the moderating effect of leader extraversion, such that the relationship between transformational leadership and employee vitality is stronger when the level of leader extraversion is high. Moreover, a moderated mediation procedure showed that the indirect effect of transformational leadership on job improvement via employee vitality was conditional to the level of leader extraversion. We highlight the original contributions of these findings by discussing the moderating role of leader extraversion as an understudied theoretical alternative to its already well-explored role as an antecedent to leadership behaviors. On a practical level, our results indicate that organizations should consider not only what leaders do (transformational leadership behaviors) but also how these behaviors are contextualized by leaders' typical approach (extraversion) to instill a maximum of positive emotion such as vitality in employees.