By Pat Anson, PNN Editor

Chronic pain sufferers are often told that physical activity and exercise can help reduce pain and improve quality of life. Now there is evidence that even light or moderate activity can have a protective effect against pain that lasts for years.

“We found that people who were more active in their free time had a lower chance of having various types of chronic pain 7-8 years later,” says Anders Årnes, a doctoral fellow at The Arctic University of Norway and University Hospital of North Norway.

“This suggests that physical activity increases our ability to tolerate pain and may be one of the ways in which activity helps to reduce the risk of developing severe chronic pain.”

Årnes is the lead author of a study, recently published in the journal PAIN, that found even light physical activity was associated with a 5% lower risk of developing chronic pain that lasts at least three months. More rigorous activity was associated with a 16% reduced risk of widespread moderate-to-severe chronic pain.

The findings are based on data from a large health survey -- the Tromsø Study --- in which over 6,800 Norwegians answered questions about their overall health, pain levels and physical activity, first in 2007-2008 and then again in 2015-2016. The average age of participants was nearly 55. Most reported some form of chronic pain, but only 5% had widespread moderate-to-severe chronic pain.

In a 2023 analysis of the survey data, Årnes and his colleagues found that people who reported vigorous physical activity had significantly more pain tolerance than those with a sedentary lifestyle.

Pain tolerance was assessed by how long they could keep a hand immersed in cold water that was a few degrees above freezing (3 degrees Celsius or 37.4 degrees Fahrenheit).

In their new follow-up study, researchers found that the ability to tolerate pain – or at least cold water -- plays a modest role in the protective effect of physical activity (PA).  

“We estimate that higher PA levels predict lower risk of chronic pain, with indications of a small mediated effect on this risk through cold pain tolerance for moderate-to-severe chronic pain states,” researchers reported.

Of course, many people with severe chronic pain are unable to exercise or fear that it will only make their pain worse. Previous studies have found that low-impact exercise programs, such as stretching while sitting in a chair, can ease pain from arthritis and other muscle and joint conditions.

“Physical activity is not dangerous in the first place, but people with chronic pain can benefit greatly from having an exercise program adapted to help them balance their effort so that it is not too much or too little,” said Årnes. “A rule of thumb is that there should be no worsening that persists over an extended period of time, but that certain reactions in the time after training can be expected.”

Even moderate physical activity can stimulate the production of endorphins and endocannabinoids – hormones and lipids naturally produced by the body -- which can relieve pain and inflammation. Regular exercise can also help us lose weight, reduce the risk of heart disease, and boost overall health.