Physical Activity as a Pain Modulator?
An estimated three-quarters of older adults in the United States have chronic pain.
Differences in levels of physical activity intensity in older adults correspond to differences in pain modulation, especially in processes that inhibit and facilitate pain, according to a study published in Pain.1
An estimated three-quarters of older adults in the United States have chronic pain. Compared with younger adults, older adults may be at higher risk for chronic pain due to age-related changes in endogenous pain processes, such as decreased pain inhibition and increased pain facilitation. Evidence suggests that increased physical activity may improve pain inhibition and facilitation, although this observation is largely based on self-reported data.2-4 This association has not been directly evaluated using objective measures of physical activity.
Researchers led by Kelly Naugle, PhD from Indiana University–Purdue University Indianapolis, investigated the relationship between objective measures of physical activity and pain inhibition and facilitation in older adults.1
A total of 51 healthy adults (≥60 years old) wore an accelerometer to measure physical activity levels over 7 days. Pain facilitatory and inhibitory functions were quantified using temporal summation of pain and conditioned pain modulation, respectively.
Sedentary time and light physical activity were associated with conditioned pain modulation (assessed using a heat pain test), with an increase in light physical activity and a decrease in sedentary time predicting greater capacity for pain inhibition.
Participants who spent more time engaging in moderate-to-vigorous physical activity had lower pain facilitation, as measured by temporal summation of pain. Sedentary time and light physical activity did not predict pain facilitation.
“More research is still needed to determine the characteristics of optimal physical activity programs for chronic pain prevention,” Dr Naugle told Clinical Pain Advisor.
Summary and Clinical Applicability
Chronic pain is prevalent in older adults, partly due to age-related dysregulation of endogenous pain processes. Researchers found that physical activity is directly related to pain inhibition and facilitation in the elderly.
“Presently and based on our results, older adults should be encouraged to meet the [American College of Sports Medicine] guidelines for exercise for older adults (150 minutes of moderate to vigorous physical activity per week). Furthermore, older adults should be encouraged to be active throughout the day with light physical activity, while minimizing prolonged sedentary time,” Dr Naugle said.
Because the study enrolled healthy older adults, the results may not be generalizable to older adults with chronic pain conditions.
- Naugle KM, Ohlman T, Naugle KE, Riley ZA, Keith NR. Physical activity behavior predicts endogenous pain modulation in older adults. Pain. 2017;158(3):383-390. doi: 10.1097/j.pain.0000000000000769
- Naugle KM, Riley JL 3rd. Self-reported physical activity predicts pain inhibitory and facilitatory function. Med Sci Sports Exerc. 2014;46(3):622-629. doi:10.1249/MSS.0b013e3182a69cf1
- Garriguet D, Tremblay S, Colley RC. Comparison of physical activity adult questionnaire results with accelerometer data. Health Rep. 2015;26(7):11-17.
- Lipert A, Jegier A. Comparison of different physical activity measurement methods in adults aged 45 to 64 years under free-living conditions [published online July 1, 2016]. Clin J Sport Med. doi:10.1097/JSM.0000000000000362