Regular exercise may reduce or prevent chronic pain: Study

The large observational study of more than 10,000 adults showed that those who consistently engaged in moderate-to-vigorous physical activity (PA) over the study period of 7 to 8 years had the highest pain tolerance. However, even light exercise was shown to be associated with greater pain tolerance.

Previous studies have shown that physical activity might affect the risk or progression of chronic pain through pain tolerance. Therefore, Anders Pedersen Årnes, Department of Pain, University Hospital of North Norway, Tromsø, Norway, and colleagues used population data from the Tromsø Study to work towards their objectives of assessing the relationship between longitudinal habitual PA change and subsequent pain tolerance and to estimate the longitudinal relationship between habitual PA and pain tolerance in repeated measurements of individuals and evaluating whether physical activity moderated any tolerance shift over time. They also assessed whether these relationships changed over chronic pain status or sex.

The study sample of 10,732 people was gathered from the sixth and seventh wave of the prospective population-based Tromsø Study, Norway. The level of leisure-time physical activity (vigorous, moderate, light, or sedentary) was derived from questionnaires. The cold-pressor test (CPT) was used to measure experimental pain tolerance. Tobit regression was used to assess the effect of longitudinal PA change on CPT tolerance at follow-up and whether a change in pain tolerance over time varied with the level of LTPA.

The study revealed the following findings:

• Participants with high consistent PA levels over the two surveys (Tromsø6 and Tromsø7) had significantly higher tolerance than those staying sedentary (20.4 s.).
• Repeated measurements show that light (6.7 s), moderate (CI 14.1 s), and vigorous (16.3 s) PA groups had higher pain tolerance than sedentary, with non-significant interaction showing slightly falling effects of PA over time.
• Being physically active at either of the two-time points measured 7–8 years apart was associated with higher pain tolerance than being sedentary at both time points.
• Pain tolerance increased with higher total activity levels and more for those who increased their activity level during follow-up, indicating that the whole PA amount matters and the direction of change.
• PA did not significantly moderate pain tolerance change over time, though estimates suggested a slightly falling effect, possibly due to ageing.

"Our findings support increased PA levels as a non-pharmacological pathway to reducing or preventing chronic pain," the researchers concluded.

Reference:

Årnes, A. P., Nielsen, C. S., Stubhaug, A., Fjeld, M. K., Johansen, A., Morseth, B., Strand, B. H., Wilsgaard, T., & Steingrímsdóttir, Ó. A. (2023). Longitudinal relationships between habitual physical activity and pain tolerance in the general population. PLOS ONE, 18(5), e0285041. https://doi.org/10.1371/journal.pone.0285041