Background: Physical activity (PA) in cancer survivors improves quality of life (QOL), functioning, fatigue, and reduces the risk of treatment complications, cancer recurrence and death. However, the optimal intervention for increasing PA is not established. Most prospective studies have shown a 6-12-week program to be an effective intervention but this is often not feasible. Therefore, we piloted a one-time individualized exercise prescription in our cardiac rehabilitation center to improve PA in cancer survivors. Methods: We prospectively enrolled cancer survivors who had completed curative intent treatment, with no evidence of active disease in this pilot study. Survivors who consented underwent a consultation with an exercise physiologist for needs assessment followed by a supervised exercise session with a tailored exercise prescription. Survivors also filled out surveys assessing their PA and QOL at baseline (bl), 3, 6 and 12 months after intervention. Clinical information was collected via chart review. We estimated longitudinal PA score and change in PA using mixed models incorporating scores from all available time points using SAS (v 9.4). Results: Between May 2018 and January 2020, 50 participants (26 lymphoma and 24 solid tumor survivors) completed the intervention. 20% participants were on maintenance therapy during the study. Clinical characteristics of 42 evaluable participants are summarized in Table. The survey response rate was 82%, 58%, 58%, 46% at bl, 3, 6 and 12 months respectively. The level of PA improved with time [mean (SE) PA score: 58.5 (4.3) bl, 63.9 (4.8) at 3, 57.6 (4.8) at 6, 62.6 (5.3) at 12 months]. The change in PA from baseline to follow-up time-points [bl vs 3m p=0.41; bl vs 6m p=0.88; bl vs 12m p=0.55] or between the lymphoma and solid tumor survivors was not statistically significant and limited by sample size. No significant trend in QOL was seen. Conclusions: Individualized exercise prescription using the cardiac rehabilitation program may be a feasible, widely applicable tool to implement a PA intervention among cancer survivors. The trend towards improvement in PA in this novel one-time intervention provides intriguing evidence and deserves future study in larger sample sizes to understand if it can improve and create sustainable PA change comparable to longer term exercise interventions.