Sprint 8® is an efficient, fat-burning high-intensity interval training (HIIT) workout that offers a complete cardio exercise experience, including warm-up and cool-down, in just 20 minutes. I created the Sprint 8 program to bring the science of intensity training to cardio workouts. This workout program has been proven to boost energy, reduce body fat, promote lean muscle mass, and improve cholesterol in just eight weeks. But it may surprise you to learn that HIIT programs, like Sprint 8, might also help fight cancer; recent findings published across multiple scientific journals suggest just that.


While HIIT programs have been shown to help burn fat and build muscle through the release of growth hormone, they also achieve an adrenal response that strengthens the immune system in a way that has recently been shown to target tumors in mice.

Scientists have known for some time that tumor-killing immune cells can attack tumors and reduce their size; and, in fact, studies in younger and older human individuals have found that exercise can increase the activity of these tumor-killing immune cells.

Still—not all exercise is created equally. The level of intensity reached appears to be critical, because regular low-intensity exercise does not reliably improve how tumor-killing immune cells function, in contrast to those who reach higher exercise intensities.

Nevertheless, researchers have still been unable to definitively say how tumor-killing immune cells find their way to the correct site in the body? Recent research suggests, however, that specific types of exercise may hold the answer.

In 2016, researchers demonstrated in a major, first-of-its-kind study that exercise intense enough to release an adrenaline surge into the body of mice will also cause the body to direct tumor-killing immune cells to the site of tumors.

During the study, some mice were blocked from their running wheel and thereby prevented from sprint cardio. These mice showed no reduced tumor size. However, the mice that did sprint cardio reduced tumor size by over 50 percent, even in the older mice. Researchers in the study linked above credit the adrenaline surge and immune-strengthening effect of sprint cardio for directing the cancer-killing immune cells to the tumors.

Dr. Pernille Hojman, spokesperson for the study, reported: “That was actually a big surprise to us. As someone working in the field of exercise and oncology, one of the main questions that cancer patients always ask is, ‘How should I exercise? Can we do anything?’ While it has previously been difficult to advise people about the intensity at which they should exercise, our data suggest that it might be beneficial to exercise at a somewhat high intensity in order to provoke a good adrenaline surge and hence recruitment of natural killer cells.”

In another experiment, Dr. Hojman’s research team injected mice with either adrenaline or a control solution (salt water). The surge of adrenaline reduced the growth of tumors by 61% in the mice that didn’t do sprint cardio. However, this was not as impressive as the mice that reduced their tumors by 74% with natural sprint cardio exercise.

So, can HIIT programs, like Sprint 8, improve our immune cells’ tumor-killing function? Further research is warranted, but recent studies suggest exercise may be among the best ways to keep yourself healthy.

Learn more

Visit Sprint8.com to learn more about the protocol and the science behind the workout program. Sprint 8 workouts are available on a wide range of Matrix cardio equipment. Matrix Fitness Systems is a Diamond Partner of NIRSA and has been an associate member of the Association since 2004. Offering a complete line of commercial fitness equipment, Matrix is dedicated to delivering the most durable products, on time, with the lowest total cost of ownership.

  • Contact Marc Loomer, National Sales Manager – Campus Recreation at Matrix Fitness to learn more about adding a line of Sprint 8-ready cardio equipment to your campus recreation facility.
A version of this article originally appeared on the Athletic Business website. | Images courtesy of Matrix Fitness.

Phil Campbell, M.S., M.A., ACSM, C-PT, FACHE, is the Sprint 8® Cardio creator, author, and Speed and Strength Coach.