The past 2 decades have witnessed a growing body of work investigating the feasibility and efficacy of exercise therapy on a broad array of outcomes in many different oncology scenarios. Despite this heterogeneity, the exercise therapy prescription approach and the dose tested has been largely similar. Thus, current exercise therapy prescriptions in the oncology setting adopt a one-size-fits-all approach. In this article, we provide an overview of personalization of exercise therapy in cancer using the principles of training as an overarching framework. Specifically, we first review the fundamentals of exercise prescription in chronic disease before focusing attention on application of these principles to optimize the safety and efficacy of exercise therapy on (1) cancer treatment-induced cardiovascular toxicity and (2) tumor progression and metastasis.