Resiliency, stress appraisal, positive affect and cardiovascular activity In accordance with the undoing hypothesis, evoked positive affect speeds up the cardiovascular system recovery in a stressful situation. An attempt was made to replicate this finding in an experimental study. Individuals characterized by high resiliency levels are capable of more efficient utilization of positive emotions in a stressful situation. Since in earlier research no relationship had been found between resiliency and a tendency to appraise stress as a challenge, this study investigated (...) a possible mediating function of a more specific dimension of cognitive appraisal, i.e. that in terms of activity-oriented challenge appraisal. The study shows that evoked positive affect does not lead to a faster recovery. However, highly resilient individuals turned out to achieve higher levels of positive affect in a stressful situation; this effect was mediated by challenge-activity appraisals. (shrink)