Can a Targeted Pre-Exercise Education Intervention Enhance the Exercise Induced Hypoalgesia (EIH) Response in Individuals With Knee Osteoarthritis (OA)?

Abstract

Objective Recent evidence suggests that education on the pain-relieving effects of exercise may enhance exercise-induced hypoalgesia (EIH) in healthy individuals. However, its impact in populations with osteoarthritis (OA), where EIH responses are more variable, remains unclear. This study examined whether positive pre-exercise education enhances EIH in individuals with knee OA.

Methods A double-blind, randomized controlled trial was conducted with 42 participants allocated to either a positive pre-exercise education group (n = 21) or a control education group (n = 21). Each group received two individual education sessions 24–72 h apart. OA- and EIH-related knowledge and beliefs were assessed pre- and post-education. EIH was evaluated following a single submaximal isometric quadriceps contraction to failure by measuring changes in pressure pain thresholds (PPTs), resting pain, and pain during stepping. Group differences were analyzed using ANCOVA.

Results The positive pre-exercise education group demonstrated greater improvements in EIH-related knowledge and beliefs compared to the control group (p = 0.001, d = 0.50, ANCOVA between-group analysis), while OA-related knowledge and beliefs remained unchanged (p = 0.34, d = 0.15). However, ANCOVA results showed no significant between-group differences in pre- to post-exercise changes in PPTs, resting pain, or pain during stepping (all p > 0.11, d = 0.04–0.25).

Conclusion Despite enhancing beliefs about exercise-induced pain relief, positive pre-exercise education did not enhance EIH compared to control education. These findings highlight the need for alternative strategies to optimize exercise-induced pain relief in OA.