Because cancer treatment can impair your balance and zap your energy, it’s generally not the time you think about finally picking up jazzercise again. But exercise is important to reduce risk of recurrence, and gentle exercise can increase energy and relaxation during treatment.
So how gentle can we go and still reap benefits? One study set out to find if a simple one-stretch flexibility routine could have an effect on breast cancer tumors even when no other treatments were present. If so, gentle stretching routines such as those in yoga, tai-chi, and qi gong may be able to help cancer patients relax and fight their tumors at the same time.
Researchers at Brigham and Women’s Hospital teamed up with researchers at Dana-Farber Cancer Institute to study the effects of gentle stretching on tumor growth in mice. They understood that physical activity provides benefits to cancer patients, but they wanted to find out more about how and why it was beneficial.
They theorized that because cancer tumors are influenced in part by the body’s connective tissue, regular stretching (which increases flexibility in the connective tissue) may have an affect on the growth of tumors. For the experiment 66 female mice were injected with breast cancer cells, and half of those injected mice were assigned to a daily stretching routine.
Since mouse-yoga was not an option, the stretch-assigned mice were gently lifted by the base of their tail so that their front paws could hold onto a bar while they were gently stretched. With a little training, the mice adapted to hold this stretch without discomfort for 10 minutes a day. This method allowed the connective tissues in each mouse’s trunk and limbs to be stretched, including the tissue surrounding the tumor. The stretch-assigned mice were stretched for 10 minutes every day for four weeks.
At the end of the four weeks, the stretch-assigned mice had tumors that were, on average, 54% smaller than the non-stretching group. The mice were provided with no other treatments beyond stretching. According to the article in Scientific Reports, “These results demonstrate for the first time that stretching reduces tumor growth in a mouse model of breast cancer.”
How Could Stretching Affect Tumor Growth?
Researchers found that stretching reduced immune system levels of PD-1, a type of “check point” that keeps the body’s immune system from fully fighting cancer. Stretching also helped reduce inflammation.
One of the study’s authors, Dr. Jean J. Zhao of Harvard Medical School and Dana-Farber Cancer Institute, is looking forward to further studies. “These results open myriad new avenues of research. There is still so much we don’t understand in terms of how stretching reduces tumor growth. Understanding these mechanisms could help us develop more effective therapies against breast cancer and potentially other cancer types,” Dr. Zhao said.
Many core yoga poses incorporate limb-stretching poses similar to the one administered to the mice, and there may be potential to use yoga or similar stretching techniques as an integrative therapy for cancer patients. Since yoga is gentle, it’s generally tolerated well by cancer patients and may benefit both a patient’s mental and emotional well-being.
Clearly, more extensive studies need to be done on the effects of stretching on tumor growth, including human studies. In the meantime, it’s exciting to think that gentle stretching, an activity many cancer patients find relaxing and soothing, may also be inhibit the growth of tumors.
Stay healthy, friends!
Katie Taylor started writing in 5th grade and hasn't stopped since. Her favorite place to pen a phrase is in front of her fireplace with a cup of tea, but she's been known to write in parking lots on the backs of old receipts if necessary. She and her husband live cozily in the Pacific Northwest enjoying rainy days and Netflix.