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Introduction: When performing an exercise or a functional test, pain that is evoked by movement or muscle contraction could be a stronger stimulus for changing how individuals move compared to tonic pain. We investigated whether the decrease in muscle force production is larger when experimentally‐induced knee pain is directly associated to the torque produced (movement‐evoked) compared to a constant painful stimulation (tonic). Methods: Twenty‐one participants performed three isometric knee extension maximal voluntary contractions without pain (baseline), during pain, and after pain. Knee pain was induced using sinusoidal electrical stimuli at 10 Hz over the infrapatellar fat pad, applied continuously or modulated proportionally to the knee extension torque. Peak torque and contraction duration were averaged across repetitions and normalized to baseline. Results: During tonic pain, participants reported lower pain intensity during the contraction than at rest (p < 0.001), whereas pain intensity increased with contraction during movement‐evoked pain (p < 0.001). Knee extension torque decreased during both pain conditions (p < 0.001), but a larger reduction was observed during movement‐evoked compared to tonic pain (p < 0.001). Participants produced torque for longer during tonic compared to movement‐evoked pain (p = 0.005). Conclusion: Our results indicate that movement‐evoked pain was a more potent stimulus to reduce knee extension torque than tonic pain. The longer contraction time observed during tonic pain may be a result of a lower perceived pain intensity during muscle contraction. Overall, our results suggest different motor adaptation to tonic and movement‐evoked pain and support the notion that motor adaptation to pain is a purposeful strategy to limit pain. This mechanistic evidence suggests that individuals experiencing prevalently tonic or movement‐evoked pain may exhibit different motor adaptations, which may be important for exercise prescription. [ABSTRACT FROM AUTHOR]

Objective To compare the effects of dry needling or manual pressure release on an active trigger point in the upper trapezius on craniocervical flexion test performance, pressure pain thresholds, and cervical range of motion in chronic neck pain. Design A parallel randomized clinical trial. Setting Physical therapy service. Subjects Individuals with chronic neck pain. Methods Subjects were randomized to receive dry needling (n = 25) or manual trigger point pressure release (n = 25) on upper trapezius active trigger points. Surface electromyography from the upper trapezius, splenius capitis, sternocleidomastoid, and scalene muscles during performance of the craniocervical flexion test was assessed before and immediately after the intervention as the primary outcome. Neck pain intensity, range of motion, and pressure pain thresholds were the secondary outcomes. Results A decrease in sternocleidomastoid activity at all stages of the craniocervical flexion test (time effect, P  < 0.001) was found in both groups after the interventions, with no significant between-group difference. Pressure pain thresholds measured over the cervical spine and second metacarpal increased after dry needling when compared with manual trigger point pressure release (P  < 0.05). Pain intensity decreased immediately after both treatments with moderate to large effect sizes, whereas cervical range of motion increased for both groups but with small effect sizes. Conclusion A single session of dry needling or manual pressure release over upper trapezius active trigger points promotes limited effects on muscle performance during the craniocervical flexion test, pressure pain thresholds, and cervical range of motion in patients with chronic neck pain. [ABSTRACT FROM AUTHOR]