2024-10-022024-10-022022-03-010047-0767https://doi.org/10.7352/IJSP.2021.52.134https://hdl.handle.net/11452/45667We aim to investigate the effect of narcissism as a personality factor on endurance performance task. We measured participants' narcissism with self report measures of the Narcissistic Personality Inventory-16 and their perception of effort via the Ratings of Perceived Exertion. We then obtained participants' psychophysiological measures such as heart rate, heart rate variability and also body mass indexes. The final sample comprised 66 individuals (Mage=18.48; SD=1.50, n=27 women, n= 39 men). All participants twice performed a multistage 20-meter shuttle run test in the same-sex teams of three: once when identifiability was low (team condition); and once when identifiability was high (individual condition). Our results revealed that narcissists' performance significantly decreased from individual to team conditions, whereas others displayed no such performance differences. Our results support the hypotheses that narcissists performed better when there was a chance for glory and socially loafed when no such opportunity was available. Results of the present study provide a sound basis foundation for future studies (i.e., endurance sports) on which to explore narcissism as individual differences in the competitive environment.eninfo:eu-repo/semantics/closedAccessHeart-ratePersonality-inventorySportCohesionAnxietyPerformanceNarcissistIndividualGroupEffortRunningSocial sciencesScience & technologyLife sciences & biomedicineHospitality, leisure, sport & tourismPsychologyPsychology, multidisciplinarySport sciencesSocial sciences - other topicsArticle00083537320000313414853210.7352/IJSP.2021.52.134