Little has been done to understand what challenges surgical patients face before surgery. Specifically, patients with multiple chronic conditions (MCC) often require prehabilitation-pre-surgery steps to improve baseline levels of health parameters required for surgery. Prehabilitation can improve health-care outcomes, reduce costs, and decrease readmissions. However, prehabilitation can be challenging for MCC patients since they need to balance chronic conditions with surgical preparation. Unsuccessful prehabilitation adherence can result in serious medical consequences including postponed surgeries and post-operative complications. In this work, we explore prehabiliation challenges faced by patients with MCC and identify opportunities for technological interventions by conducting a qualitative study of online health forum posts from 154 users. Using this data, we identified categories of patients' needs and challenges during prehabilitation.Based on our findings, we propose design recommendations to better support prehabilitation for patients with MCC.