Exercise‐induced hypoalgesia in young adult females with long‐standing patellofemoral pain – A randomized crossover study

Abstract

Background Patellofemoral pain (PFP) is a common knee pain condition where hip and knee exercises help improve treatment outcomes. This study compared the acute effect of hip versus knee exercises on anti‐nociceptive and pro‐nociceptive mechanisms in young females with long‐standing PFP. Methods In this randomized cross‐over study, 29 females with PFP performed hip and knee exercises in randomized order during a single day. Pressure pain thresholds (PPTs) were assessed by handheld pressure algometry at the patella, the tibialis anterior muscle, and the contralateral elbow. Cuff pressure algometry at the lower legs was used to assess pain detection threshold (cPDT) and tolerance (cPTT) as well as conditioned pain modulation (CPM: change in cPDT during contralateral cuff pain conditioning) and temporal summation of pain (TSP: ten painful cuff stimulations assessed on a visual analogue scale [VAS]). Results PPTs at the tibialis anterior muscle but not at the patella increased compared with baseline following both exercises (p < .002). Compared with baseline, the cPDTs and cPTTs increased after both types of exercises (p < .001). The cPTTs increased more after knee compared to hip exercises (p < .007). VAS scores for TSP were increased following hip exercises (p < .001) although the rate of VAS increase over repeated stimulations was not significantly affected by exercises. The CPM‐effect was reduced after both types of exercises (p < .001). Conclusion A general hypoalgesic response to slowly increasing pressure stimuli was observed following both hip and knee exercises as well as decreased conditioned pain modulation, potentially indicating an attenuated ability from exercise to inhibit pain.

Exercise-induced hypoalgesia after acute and regular exercise: experimental and clinical manifestations and possible mechanisms in individuals with and without pain

“…In individuals with different chronic pain conditions, the response to a single session of exercise is less consistent as hypoalgesia, reduced hypoalgesia, or even hyperalgesia (ie, increased sensitivity to pain) has been observed. As illustrated in Table 2 , hypoalgesia after exercise has, eg, been observed in individuals with chronic musculoskeletal pain, 123 , 197 shoulder pain, 105 patella femoral pain, 180 knee osteoarthritis, 59 , 194 menstrual pain, 186 and rheumatoid arthritis. 117 However, reduced EIH responses or even hyperalgesia after exercise has often been demonstrated in individuals with whiplash-associated disorder, 203 ME/CFS, 123 , 202 fibromyalgia pain, 100 , 107 , 177 painful diabetic neuropathy, 90 chronic musculoskeletal pain, 19 and also in a delayed-onset muscular soreness pain model.…”

Central Sensitization in Adolescents with Hypermobility Spectrum Disorder or Hypermobile Ehlers-Danlos Syndrome – a Feasibility Study

“…Previous studies have shown CPM to have no lasting effect (37,42). The minimum recommended interval between CPM and EIH measurements is 10 minutes (42,43). This study opted to set an interval of 15 minutes between CMP and EIH measurements.…”

The Influence of Musculoskeletal Pain On Exercise-Induced Hypoalgesia in Humans: an Experimental and Clinical Exploratory Approach

“…However, the study by Burrows and colleagues 124 suggests that pre-exercise (chronic) pain in the exercising body region may decrease EIH compared to healthy individuals. Similarly, no association between baseline pain intensity (peak pain intensity within the last week) and EIH was found in patellar tendinopathy individuals 92 . However, following EIH-inducing exercise, pain intensity may decrease in a subsequent exercise, which may indicate a link between EIH and the subsequent pain response during physical activity 189 .…”

“…However, pain may also inhibits pain in relation to exercise 37,39 suggesting that pain can facilitate EIH. Currently, the literature on the relationship between pain intensity and EIH in healthy individuals 47,55,63,71,[79][80][81][82][83][84][85][86][87] and chronic MSK pain individuals [88][89][90][91][92][93][94] show conflicting results; see Appendix A and B for schematic overviews of cross-sectional EIH studies investigating associations between EIH and pain ratings and studies comparing exercise with and without experimental pain in healthy individuals and individuals with chronic MSK pain, respectively.…”

“…EIH may be assessed during or after different types of exercise. Isometric 70,[120][121][122][123] , resistance 92,[124][125][126][127][128][129][130] , aerobic 83,85,99,116,[131][132][133] , anaerobic 81,134,135 , balance 136 and stretching 137 exercises have all been utilised in the assessment of EIH responses. Hence, no golden standard for EIH testing is currently available.…”