title: Nociceptive threshold and physical activity.
abstract: Previous studies using subjective tools to measure pain have shown that muscle exercise can have analgesic effects in man. The nociceptive leg flexion reflex (or RIII reflex) is a useful objective tool for assessing human pain. In this study, the pain threshold was assessed using the nociceptive flexion reflex in six high-level athletes 1) at rest in comparison with 8 control subjects and 2) after exercise requiring the production of a 200-Watt force over a period of 20 minutes. The nociceptive flexion reflex threshold at rest was found to be spontaneously higher in the athletes than in the controls. Physical activity resulted in a significant increase (+53%) in the threshold of the nociceptive reflex in the athletes. The role of stress-induced analgesia, the reduction in perceived intensity of stimuli during movement, and the release of opioids are discussed.
authors.affiliation: Clinique des maladies neuromusculaire et de l'appareil locomoteur, Marseille, France.
authors.forename: R
authors.initials: R
authors.lastname: Guieu
authors.forename: O
authors.initials: O
authors.lastname: Blin
authors.forename: J
authors.initials: J
authors.lastname: Pouget
authors.forename: G
authors.initials: G
authors.lastname: Serratrice
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D009619:Nociceptors / Q000502:physiology*; D012026:Reflex, Stretch / Q000502:physiology; D012146:Rest; D012684:Sensory Thresholds / Q000502:physiology*; D013177:Sports