Patterns and stability of cardiovascular responses to variations of the cold pressor test.

Test-retest reliabilities and patterns of heart rate and blood pressure responses were examined using variations in the cold pressor test in 113 normotensive white college men. Comparisons were made of stimulus site (forehead vs. foot) and bodily posture (seated vs. supine) across four separate groups of men. The stability of cardiovascular responses was examined over a 2-week-test-retest interval. Different cardiovascular response patterns emerged as a function of stimulation site and posture. Systolic and diastolic blood pressure increases were accompanied by bradycardia in the forehead cold pressor task but by tachycardia in the foot cold pressor task. Systolic blood pressure increases were larger for foot than for forehead stimulation. Heart rate increases were larger for supine than for seated men. Effects on response were independent of postural differences at baseline, and there were no stimulation site by posture interactions. The cardiovascular responses to stimulation did not attenuate across sessions in any experimental condition but were more reliable for foot than for forehead stimulation and for supine than for seated posture. Short-term stability for changes to the task approached that for baseline and task and was higher than has been reported elsewhere.