Psychological and neuroendocrine responses to social stress and to the administration of the alpha-2-receptor antagonist, yohimbine, in highly trained endurance athletes in comparison to untrained healthy controls

Pharmacopsychiatry. 2011 Jun;44(4):129-34. doi: 10.1055/s-0031-1277166. Epub 2011 Jun 27.


Introduction: Several clinical studies suggest antidepressive and anxiolytic effects of regular endurance training. The mechanisms by which exercise exerts these effects are still unclear. It was hypothesized that athletes might show a diminished reaction to psychosocial stress and noradrenergic stimulation.

Methods: 12 male athletes and 12 healthy untrained male controls underwent a challenge paradigm on 3 separate days: the alpha-2-receptor antagonist yohimbine (0.4 mg/kg), placebo or a psychosocial stress test (SST) were administered. Responses were measured by psychometric scales, plasma cortisol, blood pressure and heart rate.

Results: Before testing, psychometric variables and cortisol levels were not different between the 2 groups. In comparison to placebo conditions, both the social stress test and the administration of yohimbine were followed by significant increases of anxiety symptoms, plasma cortisol, heart rate and blood pressure in both groups. However, these responses were not significantly different between the group of athletes and the control group.

Discussion: These results do not support the hypotheses that high aerobic fitness is associated with attenuated psychological and neuroendocrine responses to yohimbine or to psychosocial stress.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic alpha-2 Receptor Antagonists / toxicity
  • Adult
  • Anxiety / blood
  • Anxiety / chemically induced
  • Anxiety / prevention & control*
  • Anxiety / psychology
  • Athletes / psychology*
  • Behavior / drug effects
  • Blood Pressure / drug effects
  • Double-Blind Method
  • Germany
  • Heart Rate / drug effects
  • Humans
  • Hydrocortisone / blood
  • Interpersonal Relations
  • Male
  • Neurosecretory Systems / drug effects
  • Physical Endurance
  • Physical Fitness / physiology*
  • Physical Fitness / psychology*
  • Psychiatric Status Rating Scales
  • Stress, Physiological / drug effects*
  • Stress, Psychological / physiopathology*
  • Yohimbine / adverse effects*


  • Adrenergic alpha-2 Receptor Antagonists
  • Yohimbine
  • Hydrocortisone