Background: Chronic pain is defined as pain for at least 3 months and is highly prevalent in society (10-30%). Individuals with chronic pain are more sensitive to pressure pain and have a disturbed pain perception. Physical activity (PA) has been shown to be a helpful method to treat and decrease disability in these individuals, but the knowledge about the relationship between chronic pain, PA and aerobic capacity is less understood. The aim of this study was to investigate if pain experience is associated with aerobic capacity and physical activity in a population with chronic pain in comparison to a pain free reference group.

Method: 146 men and women between 40 and 70 years old participated. Pressure pain sensitivity was measured with an Algometer on eight points and aerobic capacity was measured with Ekblom-Bak submaximal test on a bicycle ergometer. A questionnaire was used to gather information about self-reported PA, pain regions and fear-avoidance.

Result: Individuals with chronic pain had significantly lower pain thresholds (p=0.028) and higher fear-avoidance score (p=0.001), but no difference in aerobic capacity compared to pain-free individuals (p=0.344). Women had lower thresholds compared to men in both chronic pain and pain-free group (p<0.001 and p=0.008). There were no association between aerobic capacity and self-reported moderate PA (r=0.001) or in vigorous PA (r=0.173). Low VO_2max has more pain regions (p=0.017) and lower pain thresholds (p=0.001) compared with high VO_2max, but no difference in fear-avoidance score (p=0.234).

Conclusion: Individuals with chronic pain had a higher sensitivity to pressure pain and a higher fear-avoidance compared to pain-free individuals, but no difference in aerobic capacity. There were no associations between self-reported PA and aerobic capacity, and individuals with low VO_2max had more pain regions and lower pain thresholds compared with individuals with high VO_2max, but no differences in fear-avoidance was found.