There is increasing recognition of the importance of maximizing program-setting fit in scaling and spreading effective programs. However, in the context of hospital-based mobility programs, there is limited information on how settings could consider local context and modify program characteristics or implementation activities to enhance fit. To fill this gap, we examined site-initiated adaptations to STRIDE, a hospital-based mobility program for older Veterans, at eight Veterans Affairs facilities across the United States. STRIDE was implemented at eight hospitals in a stepped-wedge cluster randomized trial. During the pre-implementation phase, sites were encouraged to adapt program characteristics to optimize implementation and align with their hospital's resources, needs, and culture. Recommended adaptations included those related to staffing models, marketing, and documentation. To assess the number and types of adaptations, multiple data sources were reviewed, including implementation support notes from site-level support calls and group-based learning collaborative sessions. Adaptations were classified based on the Framework for Reporting Adaptations and Modifications-Enhanced (FRAME), including attention to what was adapted, when, why, and by whom. We reviewed the number and types of adaptations across sites that did and did not sustain STRIDE, defined as continued program delivery during the post-implementation period. A total of 25 adaptations were reported and classified across seven of the eight sites. Adaptations were reported across five areas: program documentation (n = 13), patient eligibility criteria (n = 5), program enhancements (n = 3), staffing model (n = 2), and marketing and recruitment (n = 2). More than one-half of adaptations were planned. Adaptations were common in both sustaining and non-sustaining sites. Adaptations were common within a program designed with flexible implementation in mind. Identifying common areas of planned and unplanned adaptations within a flexible program such as STRIDE may contribute to more efficient and effective national scaling. Future research should evaluate the relationship between adaptations and program implementation.