new research suggests.
In a large observational study of more than 10,000 adults, researchers found those who consistently engage in moderate to vigorous physical activity over the 7- to 8-year study period reported the highest pain tolerance. However, the results also showed that even light exercise was associated with greater pain tolerance.
“There were indications that both total amount of physical activity over time, as well as the direction of change in activity level over time matters to how high your pain tolerance is,” lead investigator Anders Pedersen Årnes, PT, MPH, research fellow and adviser at the University Hospital of North Norway, affiliated with the University of Tromsø, said in an interview. “As an observational study, this points toward the possibility that increased physical activity might increase pain tolerance.”
The findings were published online in PLOS One.
Anything is better than nothing
The researchers drew from the prospective, population-based Tromsø health study, a health survey that draws on surveys conducted periodically since 1974 among residents in northern Norway.
The study included 10,732 participants who completed surveys in 2007-2008 and again in 2015-2016.
Data on physical activity, experimental pain tolerance, sex, sociodemographic covariates, and chronic pain was collected through questionnaires, biological samples and clinical examination.
Pain tolerance was measured using the cold-pressor test (CPT), in which participants submerge their hand in icy water for as long as possible.
CPT tolerance was 7%, 14%, and 16% higher respectively for light, moderate, and vigorous consistent exercise across the two surveys versus the sedentary group.
“Engaging in habitual physical activity in leisure time is associated with higher pain tolerance,” Mr. Årnes said. “Any kind of activity over time is better than being sedentary.”
The researchers also found that people who were sedentary at baseline who reported greater physical activity at follow-up also had higher pain tolerance than those who remained sedentary, although this finding was not statistically significant.
This highest pain tolerance was noted in people who engaged in moderate to vigorous exercise over time, with a 20.4-second longer performance in the CPT than those who were consistently sedentary (P < .001; 95% confidence interval, 13.7-27.1).
There was no significant difference in pain tolerance between men and women and all participants experienced a decline in tolerance over time.
“Results indicate that a positive change in physical activity level over time was associated with higher pain tolerance,” Mr. Årnes said. “Your total activity level might decide how much, as more seems to be better.”
More work needed
The long follow-up and large number of patients are two strengths of the study, Steven Cohen, MD, chief of pain medicine and professor of anesthesiology, neurology, physical medicine & rehabilitation and psychiatry at Johns Hopkins University, Baltimore, said in an interview.
“This study explored the relationship between general physical activity levels and one form of acute pain, but data from other studies show a benefit for other forms of pain,” said Dr. Cohen, who was not part of the research. “Taken together, this suggests that exercise is beneficial for individuals living with pain.”
The findings demonstrate an association between exercise and pain tolerance and other research has shown evidence of a cause-and-effect relationship, Dr. Cohen said. However, “more work is needed to determine what mediates these effects.”
Questions also remain about how exercise might impact tolerance or risk for chronic pain, he added.
Investigators are now working on a follow-up study of how the effect of exercise on pain tolerance might influence chronic pain risk, Mr. Årnes said.
The study received no specific funding. Mr. Årnes and Dr. Cohen reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.