Espinoza, Sarah2021-02-222021-02-222020-12https://hdl.handle.net/11299/218721University of Minnesota Ph.D. dissertation. December 2020. Major: Kinesiology. Advisor: Diane Wiese-Bjornstal. 1 computer file (PDF); viii, 124 pages.Sport is an important context in adolescent development. A wealth of research has investigated how the experiences young people have and relationships they build within sport impact their self-perceptions, specifically, their global self-worth. Understanding how global self-worth can be affected by athletic experiences has been key to designing psychologically safe and promotive physical activity spaces, and such research (largely guided by Harter’s mediational model) has informed pedagogy and practice in sport settings and physical education. One adolescent sport context—ultimate—has been left out of this work, though it has tens of thousands of youth participants in the United States and abroad. Extant research on youth sport and global self-worth may not be immediately applicable to understanding ultimate, as ultimate has a unique body of participants, refereeing system, culture, and je ne sais quoi from other sports. Thus, the purpose of this study was to explore sociodemographic and psychological differences in adolescent ultimate players’ global self-worth. Participants (N = 380, mean age = 17.1 years) completed measures of global self-worth, perceived athletic and social competence, perceived social support, and sociodemographic information at a single timepoint. Hierarchical regression analyses indicated that identifying as a boy, identifying as Caucasian/White rather than Asian/Asian American, and having higher perceived ultimate competence, social competence, and social support from parents significantly predicted variance in participants’ global self-worth. No significant relationships were found between global self-worth and years of experience in ultimate, highest level of ultimate played, playing on single-gender or mixed-gender ultimate teams, or perceived social support from ultimate coaches, teammates, or opponents. In sum, being good at ultimate, able to make friends and fit in with peers, and feeling valued by one’s parents contribute to adolescent ultimate players’ global self-worth. Youth ultimate programs should take steps to give participants the best possible chances of having adaptive self- worth by sustaining their feelings of competence and support.enadolescentperceived competenceself-worthsocial supportsportultimate frisbeeThesis or Dissertation