The purpose of this study was to examine how pre-service teachers (PSTs) develop their teaching adaptive competence through teaching rehearsal and repeated teaching, which is one of the focused teacher education strategies in practice-based teacher education (PBTE). This study was conducted in an introductory teaching methods course of a physical education teacher education (PETE) program. A total of 22 PSTs participated in the study. Fourteen were male, and eight were female. The PSTs had varied coaching experiences ranging from little to no coaching in limited recreational sports settings, and none had teaching or coaching experience in the school setting. A total of 150 lesson plans (three different lesson plans per PST that were revised across five weeks) and 85 teaching videos (five peer-teaching sessions) were collected and analyzed to examine PSTs' adaptive competence in the lesson plans and enacted teachings. First, PSTs' lesson plans were analyzed by the total number of adaptations, the number of adaptations to each Core Practice, and the number of types of adaptations. Second, PSTs' teaching videos were explored by the number of adaptations (add and miss), and errors. Last, it was examined whether there are relationships between PSTs' teaching adaptations demonstrated in lesson plans and errors in enacted teaching. The results showed that PSTs created a wide-ranged number of adaptations to lesson plan one to three (lesson plan one [Median=38.50, range 6-101]; two [Median=49.00, range 14-184]; three [Median=38.00, range 18-97]). The PSTs made the most adaptations to Core Practice two (providing clear instruction) followed by one (establishing rules and routine) and five (building positive relationships with students); minimum adaptations were made to Core Practices three (breaking down the content into smaller elements) and four (checking students' understanding). Also, the majority of teaching adaptations made by PSTs were type two (refine) adaptations, and a minimal number of teaching adaptations were made for types one (modify) and three (apply). Relative to teaching, the results showed that PSTs were able to make teaching adaptations (add and miss) in enacted teaching that was not on their lesson plans, and PSTs showed fewer errors in enacted teaching as they progressed from week one to five. Last, Spearman's rho analysis showed that there were no relationships between PSTs' adaptations to their lesson plans and errors in enacted teaching. Preservice teachers developed their teaching adaptive competence in lesson plans and enacted teaching through teaching rehearsals and repeated teaching in authentic settings with the use of teaching scenarios, quality supervisors' feedback, and structured reflection. In conclusion, PBTE is an effective framework for promoting PSTs' teaching adaptive competence in lesson planning and enacted teaching. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]