Does Exercise Decrease Pain via Conditioned Pain Modulation in Adolescents?

Abstract

Purpose: Pain relief after exercise, exercise-induced hypoalgesia (EIH), is established across the lifespan. Conditioned pain modulation (CPM: pain inhibits pain) may be a mechanism for EIH.

Methods: In 55 adolescents, pressure pain thresholds were measured before and after exercise (deltoid, quadriceps, and nail bed) and during CPM at the nail bed and deltoid test stimulus sites. The relationship between EIH and CPM was explored.

Results: EIH occurred at deltoid and quadriceps; CPM occurred at nail bed and deltoid. CPM and EIH correlated at deltoid; adolescents with greater CPM experienced greater pain relief after exercise. At this site, CPM predicted 5.4% of EIH. Arm lean mass did not add a significant effect. Peak exercise pain did not influence EIH. Adolescents with none, minimal, moderate, or severe peak exercise pain experienced similar EIH.

Conclusions: A potential relationship exists between CPM and EIH in adolescents. Pediatric physical therapists should consider the CPM response when prescribing exercise as a pain management tool.

Conflict of interest statement

Statement: The authors declare no conflict of interest.

Figures

Figure 1. Relation of Exercise Induced Hypoalgesia and Conditioned Pain Modulation

Exercise induced hypoalgesia experienced at the deltoid muscle is positively correlated with conditioned pain modulation at the deltoid muscle (r=0.27, p=0.05).

Figure 2. Exercise Induced Hypoalgesia by Peak Exercise Pain Groups

Pre and post exercise pressure pain thresholds (EIHDeltQuad) shown by peak exercise pain groupings (no pain, n=9; minimal pain, n=14; moderate pain, n=18; severe pain, n=14). EIH was similar between the peak exercise pain groups (trial x peak pain: p>0.05).