Background: Physical activity and exercise appear to benefit patients receiving preoperative treatment for cancer. Supports and barriers must be considered to increase compliance with home-based exercise prescriptions in this setting. Such influences have not been previously examined. Methods: The authors used quantitative and qualitative methods to examine potential physical activity influences among patients who were prescribed home-based aerobic and strengthening exercises concurrent with preoperative chemotherapy or chemoradiation for pancreatic cancer. Physical activity was measured using exercise logs and accelerometers. Social support for exercise and perceived neighborhood walkability were measured using validated surveys. Relationships between influences and physical activity were evaluated using linear regression analyses and qualitative interviews. Results: Fifty patients received treatment for a mean of 16 (9) weeks prior to planned surgical resection. Social support from friends and neighborhood esthetics were positively associated with physical activity (P < .05). In interviews, patients confirmed the importance of these influences and cited encouragement from health care providers and desire to complete and recover from treatment as additional motivators. Conclusions: Interpersonal and environmental motivators of exercise and physical activity must be considered in the design of future home-based exercise interventions designed for patients receiving preoperative therapy for cancer.