At the recent American Association of Cancer Researchers (AACR,) there was a shocking poster presentation that demonstrated that mice that exercised experienced implanted prostate cancer tumor grow that was twice as fast than did those mice who were restricted from exercising! The study was conducted by the Duke Comprehensive Cancer Center (DCCC) and the Duke Prostate Center.

According to Lee Jones, Ph.D., a researcher in the DCCC and senior investigator on this study, “Our study showed that exercise led to significantly greater tumor growth than a more sedentary lifestyle did, in this mouse model. Our thought is that we may, in the future, be able to use this finding to design better drug delivery models to more effectively treat prostate cancer patients, and those with other types of cancer as well.”

The study design had 50 mice implanted with prostate cancer tumor cells. Half of the mice were allowed to exercise on wheels in their cages while the other half were not provided any means of exercise. All the mice were fed the same diet. On average, the exercising mice ran more than half a mile each day.

The researchers found that the mice that had the opportunity to exercise had tumor growth that was approximately twice as fast as the mice who did not have access to exercise wheels.

One of the major problems in delivering chemotherapy and radiation to tumors is poor blood flow. These findings may be applicable to future methods of drug delivery systems. Improving the blood flow to tumors may allow better distribution at higher rates of chemotherapy drugs.

The researchers are currently conducting a validation study.

The researchers have made a significant warning for men with prostate cancer to not interpret these findings as an endorsement for not exercising. They pointed out that the mice in the study were not receiving treatment and the study still needs to be validated.

Additionally, it is well established that the positive benefits of exercise far out weight the additional risk of tumor growth. Exercise provides significant positive benefits for the cardiovascular system, on Type II diabetes, obesity, and many other chronic conditions.

Joel T Nowak MA, MSW