Physical activity has a positive effect on people living with cancer regardless of intensity, according to a study conducted by researchers at Uppsala University in Sweden and published in the Scandinavian Journal of Medicine and Science in Sports. In other words, light exercise and heavy exercise have similar benefits.
Multiple international studies have found that physical activity improves the mental and physical health of people receiving treatment for cancer. Among other benefits, exercise reduces the risk of common side effects, such as fatigue, nausea, anxiety and depression. But so far, these studies haven’t identified whether the intensity of such activity affects the benefits. To fill this knowledge gap, the Uppsala University researchers launched the randomized clinical trial Phys-Can, a portmanteau of the words “physical training and cancer.”
The researchers recruited 577 people between ages 30 and 84 who had recently been diagnosed with breast cancer, prostate cancer or colorectal cancer to participate in a fitness program. The program, which consisted of resistance training at Sweden’s largest fitness club and endurance training at home, ran for six months. Participants trained at either high intensity or low-to-moderate intensity. In addition, half received extra support, including assistance with planning endurance training sessions and recording the results.
For the low-to-moderate- intensity group, the strength training involved lower weights, and the endurance goal was at least 150 minutes a week of activities such as walking or biking. For the high-intensity group, strength training meant higher weights, and endurance work included two interval training sessions twice each week. Interval training, which has certain fitness benefits, entails alternating short bursts (such as 30 seconds) of intense activity with longer intervals of less intense activity.
At the end of the program, the researchers identified no “clinically relevant” differences between the high-intensity and low-to-moderate-intensity arms and no differences at all between the no-support and extra-support arms, lead study author Ingrid Demmelmaier, an associate professor of physiotherapy, said in a press release.
“The conclusions we draw from the study are first, that whether the training is of high or low-to-medium intensity doesn’t seem to matter much,” Demmelmaier said.
While those in the high-intensity arm did score a little higher on measures of energy, physical fitness and leg-muscle strength, Demmalmaier noted, those differences were not considered significant because they were not “likely to make a difference in the patients’ everyday life.”
The study is ongoing. Next, the researchers plan to assess the longer-term effects of the training program on participants’ health.
For more on how exercise can reduce fatigue during or following cancer treatment, read “Strategies to Improve Cancer-Related Fatigue Symptoms.” And for more on the wholesale benefits of exercise, read “Exercise Is Medicine” and “Prescribing Exercise as Cancer Treatment.”