While the benefits of exercise on overall health are widely documented, little is known about how exercise affects the progression or treatment of malignant neoplasms. Tumors have a complex vascular network which is likely affected by the global changes in hemodynamics and perfusion that occur during moderate exercise. Increased tumor oxygenation is clinically relevant as it may counteract the hypoxic tumor environment which is known to contribute to resistance to chemo- and radiation therapies, angiogenesis, invasiveness and metastasis, genomic instability, and resistance to cell death.