The personality trait openness to experience has been implicated in health, and in particular cardiovascular wellbeing. In a sample of 62 healthy young female adults, the role of openness in cardiovascular responsivity during a stress exposure was examined. Traditionally, methodologies have averaged a stress exposure into a single reading. This may be limited in that it does not consider patterns of cardiovascular adaptation within a stress exposure. Continuous cardiovascular data were reduced to mean 10 second readings, with phases determined through examinations of shifts in responsivity between each 10 second pairing. Analyses revealed a significant linear interaction for openness across the entire exposure for systolic blood pressure, and cardiac output. A significant between-subjects effect for heart rate also emerged. Contrary to their lower counterparts, those highest in openness exhibited an increasingly myocardial hemodynamic response profile throughout the exposure. Comparisons of responsivity suggests adaptive stress response trajectories for those highest in openness. This study also provides evidence that an attenuation of myocardial responsivity may underpin blunted responsivity. This study provides a potential mechanism in reported openness-health associations.