Explicit education about exercise-induced hypoalgesia influences pain responses to acute exercise in healthy adults: A randomized controlled trial

The mechanisms through which acute exercise reduces pain (ie, exercise-induced hypoalgesia [EIH]) are poorly understood. This study aimed to determine if education about EIH affected pain responses after acute exercise in healthy adults. Participants received 15 minutes of education either about EIH (intervention, n = 20) or more general education about exercise and pain (control, n = 20). After this, the participants’ knowledge and beliefs about exercise and pain were assessed. Pressure pain thresholds were then measured before and after 20 minutes of cycle ergometer exercise. Compared with the control group, the intervention group believed more strongly that pain could be reduced by a single session of exercise (P = .005) and that the information they had just received had changed what they thought about the effect of exercise on pain (P = .045). After exercise, pressure pain threshold increased in both groups, but the median increase was greater in the intervention group compared with the control group (intervention = .78 kg/cm2, control = .24 kg/cm2, P = .002, effect size [r] of difference = .49). These results suggest that cognitive processes in the appraisal of pain can be manipulated to influence EIH in healthy adults