Opioid System Cerebral Activity in Endurance Sportswomen - Addiction or Denutrition ? [11C]Diprenorphine PET Study

Abnormal opioid system have been identified in addictive behavior and activity of the opioid system has also shown a strong link with the nutritional balance. A significant increase in endorphin levels was noticed after exercise, proportional to the duration and intensity of this activity. One brain imaging study showed an increase in opioid activity in athletes after endurance training. However , a decrease in opioid tone related to receptor desensitization in the brain has been raised in the sport and it is possible to feel like , the subject must perform physical exercise more frequently . Consequently, in order to deepen the hypothesis of addiction in high-level sport , the brain opioid activity should be assessed pre- training compared to a group of sedentary control subjects .

Preliminary results of a previous study the investigators are conducting on anorexia nervosa (AN ) show abnormalities that appear to be involved in self addiction anorexia nervosa and the regulation of gonadal function. However, the relation of cause and effect between these anomalies and undernutrition remains to be determined . Given the addictive component in the endurance sport and the variability of the nutritional status of its practitioners , evaluation of brain activity in these subjects could provide additional answers.