New research provides further evidence that staying active could play a serious preventive role.
- Exercise has been linked to a reduced risk of certain kinds of cancer. And now, new research suggests that high-intensity interval training, or HIIT, may help thwart the growth of cancer cells, too.
- Researchers determined that even a single session of HIIT was effective at reducing the growth of colon cancer cells.
- While the study was performed in cancer survivors, researchers believe the same findings may apply to others as well.
Consistent, long-term physical activity has been linked to reduced risk for several types of cancer, thanks to the way exercise reduces inflammation, improves immune system function, and lowers levels of certain hormones related to cancer development.
But you don’t need to log years of effort to get the cancer-fighting benefits: A new study published in the Journal of Physiology suggests that even a single session of high-intensity interval exercise may significantly slow the growth of colon cancer cells.
Researchers recruited male colorectal cancer survivors, and had them complete either one HIIT session or do HIIT training regularly. The single-session group did a 10-minute warmup before four rounds of cycling, each for four minutes, with three minutes of recovery time in between. The short-term training group did this protocol three times a week for a month.
Immediately before and after each exercise session, researchers collected blood samples. They replaced the serum—what’s left once red blood cells are removed—of cancer cells grown in a lab with the serum from the participants to see how exercise affected the cell growth.
Serum collected before exercise didn’t reduce colon cancer cell growth, but the serum taken after that single cycling session? That squashed the growth of the cancer cells immediately, suggesting that HIIT may change the environment of the cells, so they are less likely to grow unchecked.
The serum collected from the training group showed no significant differences, meaning they didn’t have more cancer-stopping power compared to the single-session group.
Researchers found there were elevations in some inflammatory markers, known as cytokines, immediately after exercise, and hypothesized that this is what played the biggest role in cell growth reduction, according to lead researcher James Devin, Ph.D., an exercise physiologist at the University of Queensland.
“During exercise, muscle becomes a primary source for releasing inflammatory cytokines markers, known as myokines,” he told Runner’s World. “We know that higher intensity exercise promotes a much greater myokine response compared to moderate intensity exercise.”
Although the recent study involved only colon cancer survivors, Devin said that the reduction in cancer cell growth is likely not specific only to those who’ve had cancer before. He noted that other research using similar techniques and serum from healthy individuals has found reductions in the growth of prostate cancer cells.
“There will always be subtle differences in how individuals respond to exercise,” he said. “And we are still a long way from understanding how these responses observed in the laboratory may influence human colorectal tumors. But the current results are very exciting, and suggest the acute effects following every single session of exercise are of great importance.”