Introduction
Exercise oncology services are evidence based and aim to reduce symptom burden and potentially improve outcomes in adults living with and beyond cancer. Healthcare system-based exercise oncology programs include exercise prior to, during, and after treatment, but the implementation and maintenance of these programs are not well documented. We aimed to describe five healthcare system-based exercise oncology programs in the United States, including service information and barriers to and facilitators of program success.

Methods
This was a qualitative case study of five healthcare-based exercise oncology programs in the United States informed by the Exploration, Preparation, Implementation, Sustainment framework. We conducted semistructured online interviews with the founders and other key representatives of each program assessing program structure, adoption, and integration into the healthcare system. Data were evaluated using qualitative descriptive methodology.

Results
In each healthcare-based exercise oncology program, trained exercise professionals delivered in-person, virtual, or hybrid exercise programs to adults with cancer. Buy-in from healthcare system leadership, clinicians, and administration was key to success. All programs were designed to meet the needs of the individual healthcare systems. Institutionalization of the programs into existing healthcare systems facilitated sustainment. Length and exercise prescription for each program varied, but individually tailored exercise programs with physical or functional assessments (often pre/post) were reported by most programs. Funding was a common barrier.

Conclusions
Institutional priorities and buy-in from both leadership and clinicians were used to establish and maintain five healthcare-based exercise oncology programs from across the United States. These programs followed evidence-based recommendations provided by exercise professionals within the healthcare system to serve patients from the healthcare system’s catchment area. Healthcare systems exploring the creation of exercise oncology programs should consider institutional structures, provider priorities, resources (e.g., staff, finances), leadership buy-in, and financial support.