Regular muscle-strengthening exercises associated with aerobic activities can reduce cancer mortality, according to a systematic review of epidemiologic studies published by Nascimento et al in the International Journal of Behavioral Nutrition and Physical Activity. Workouts with activities like squats, rowing, planks, and weight training may reduce the probability of dying from cancer by 14%. When these exercises are combined with aerobic activities, the benefit is even greater, potentially reducing mortality by 28%.
“Physical activity has been associated with a reduced risk of several types of cancer, but it was unclear what kinds of exercise had the best results. In our study, we found evidence that muscle strength training can not only reduce cancer incidence and mortality but also have an even better effect when associated with aerobic activities, such as walking, running, swimming, and cycling,” said study coauthor Leandro Rezende, ScD, Professor in the Department of Preventive Medicine at the Federal University of São Paulo’s Medical School (EPM-UNIFESP) in Brazil.
Epidemiologic research using demographic data has shown that physical activity in general reduces the risk of breast, endometrial, stomach, throat, kidney, and bladder cancers. The EPM-UNIFESP study found that muscle-strengthening exercises can reduce the risk of kidney cancer by 26%. Statistically significant correlations were not found between muscle-strengthening exercises and colon, prostate, lung, pancreatic, bladder, esophageal, and rectal cancers, as well as melanoma, multiple myeloma, lymphoma, leukemia, and cancers of the digestive system, owing to the limited number of studies.
The study also corroborated the recommendations of the World Health Organization (WHO) regarding regular aerobic exercise for adults: 150 to 300 minutes per week if moderately intense, 75 to 150 minutes if vigorous, or an equivalent combination. The WHO also recommends twice-weekly strengthening exercises.
“The WHO’s recommendations are based on a number of benefits to health from physical activity, and our review of the literature showed that a reduced risk of dying from cancer is another benefit,” Dr. Rezende said.
The researchers analyzed 12 studies involving 11 cohorts and a control case, with participation by a total of 1,297,620 people, who were monitored in studies lasting between 6 and 25 years. The analysis suggested that strength training twice a week can protect against cancer.
Most studies of exercise and cancer prevention focus on aerobic activities, Dr. Rezende noted, while muscle strengthening is typically part of workouts designed to build muscle mass or treat specific health problems such as high blood pressure or cardiovascular disorders.
“Four years ago, we conducted a study that associated strength training with a reduced risk of cancer. Meanwhile, other studies have been published, and we thought it would be interesting to undertake a systematic review of this literature in order to appraise all the evidence on this relationship,” he said. “However, we went further to show that the benefits of muscle strengthening exercises in terms of reducing cancer incidence and mortality can be magnified when they’re combined with aerobic exercises.”