Moderate Exercise Helps Cancer Treatments Work More Effectively

Researchers at Kansas State University have discovered that moderate exercise on a regular basis can improve radiation treatments in cancer patients.

"If we can increase the efficacy of radiation treatment, then the patient's prognosis is enhanced," researcher Brad Behnke said in a news release. "An intervention like exercise has almost universally positive side effects versus other treatments that can have deleterious side effects. Exercise is a type of therapy that benefits multiple systems in the body, and may permanently alter the environment within the tumor."

As it stands, the National Cancer Institute at the National Institutes of Health recommends exercise for cancer patients and cancer survivors. Yet little research has shown just what can happen within tumors during exercise.

For the latest study, researchers worked to enhance oxygen delivery to tumors. Behnke described more aggressive tumors as being hypoxic and having low oxygen. Yet because oxygen is a "radiosensitizer," it can also help to destroy cancer cells, resulting in low-oxygen tumors that are resistant to traditional cancer therapies like radiation.

"If we manipulate all the systems in the body -- the lungs, the heart and the blood vessels -- with exercise, we can take advantage of the dysfunctional vasculature in the tumor and enhance blood flow to the tumor," Behnke added. "The tumor becomes the path of least resistance for the elevated cardiac output of exercise, which results in a substantial increase in tumor oxygenation during and after exercise."

Findings seemed to show that the key is simply moderate exercise. Little to no exercise would have no effect, while too much exercise could be too strenuous on the body and shut down blood flow to the tumor region by impairing the immune system. (Moderate exercise might include 30 to 60 percent of someone's aerobic capacity, including a brisk walk or a slow jog.)

"There really aren't any negative side effects of moderate-intensity exercise," Behnke concluded. "Exercise is often prescribed to improve the side effects of cancer and treatment, but what exercise is doing within the tumor itself is likely beneficial as well."

For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).