My new book, Deep Fitness: The Mindful, Science-Based Strength-Training Method to Transform Your Well-Being in 30 Minutes a Week, coauthored with Philip Shepherd, is coming out on October 12, 2021. The following is an adapted excerpt from the book. If you want to learn more, pre-order now!
It seems everyone’s life has been touched by cancer, either personally or through someone they know. In 2018, the World Health Organization reported that 14 million new cases are documented annually, many associated with a sedentary lifestyle.
In fact, studies have shown that the lower the strength and mass of your muscles, the higher your risk of dying from cancer. In a UK study of 80,000 adults over 30, people who performed two strength-training sessions per week had a 34% reduced risk of dying from cancer. By contrast, adhering to the UK guidelines for aerobic exercise—150 minutes per week moderate or 75 minutes per week vigorous exercise—provided no statistical benefit. Furthermore, the study found that cancer survivors who did strength training at least once a week had a 33% reduced risk of death from any cause.
Strength training helps combat many conditions that increase the risk of cancer—such as insulin resistance, chronic inflammation, and visceral fat. It also promotes conditions that decrease the risk of cancer, such as the functioning of the immune system.
Interleukin-6, a chemical messenger that is produced by strength training, reduces tumor volume by supporting the infiltration of tumors by natural killer cells. Curiously, this effect has only been observed as a consequence of exercise: when interleukin-6 was administered intravenously, it had no observable effect on tumor growth.
Strength training also lowers the risk of cancer by activating two players that are crucial to cellular health. They might be dubbed “the executioner” and “the clean-up/recycling squad.” The executioner, scientifically referred to as apoptosis, programs appropriate cell death. When cells don’t die on schedule, that can result in the proliferation of tumor cells. The clean-up/recycling squad gathers cell debris and recycles it to help generate new, young cells in a process known as autophagy. Like apoptosis, it is also induced by exercise.
Researchers are constantly learning more about how muscle might help prevent cancer, but for now the findings are promising for those of us who engage in regular strength training.