The aim of the present thesis was to investigate the impact of implicit aging on effort mobilization based on an extension of the effort-related predictions of the Implicit-Affect- Primes-Effort (IAPE) model (Gendolla, 2012, 2015). The IAPE model posits that affective stimuli that are implicitly processed during performance on a task influence effort mobilization through their impact on subjective demand according to the principles of motivational intensity theory (Brehm & Self, 1989). The present work tested whether the IAPE model logic could be generalized to other concepts that are associated with ease and difficulty than the affective ones. Thus, activation of the aging stereotype in the context of cognitive tasks should render the idea of performance difficulty accessible, leading to experiences of high task demand and influence effort mobilization. Four experiments were conducted to test the idea that the mere activation of the aging stereotype could systematically influence young individuals' effort-mobilization.