Background Gait speed is a reliable measure of physical function and frailty in patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). Slow gait speed pre-TAVR predicts worse clinical outcomes post-TAVR. The consequences of improved versus worsened physical function post-TAVR are unknown. Methods and Results The REPRISE III (Repositionable Percutaneous Replacement of Stenotic Aortic Valve Through Implantation of Lotus Valve System-Randomized Clinical Evaluation) trial randomized high/extreme risk patients to receive a mechanically-expanded or self-expanding transcatheter heart valve. Of 874 patients who underwent TAVR, 576 with complete data at baseline and 1 year were included in this analysis. Slow gait speed in the 5-m walk test was defined as https://www.clini​caltr​ials.gov; Unique identifier: NCT02202434.