It is generally known that changes in body posture may induce complex cardiovascular and hormonal activation. The present work was aimed at verifying the hypothesis that changes in body posture contribute to cardiovascular and hormonal responses during mental stress tests and thus interfere with the effect of the psychosocial component of the stress procedure. In young healthy males, we studied the influence of a public speech test that includes postural changes (n=9) and of the postural maneuver per se (n=8), on hemodynamics, plasma hormone levels and salivary cortisol. Both public speech and postural changes significantly elevated heart rate, blood pressure, and plasma noradrenaline. Significant effects on adrenocorticotropic hormone, cortisol and adrenaline were seen with public speech only. The alterations induced by postural changes were much smaller than those seen following mental stress procedure. This study provides evidence that whenever psychological stress tests are applied, possible confounding postural influences on hemodynamic and endocrine responses are to be considered. Supported by SP51/0280800/0280802, partially by VEGA 5064, European Social Fund and SAIA.