Hemodynamic responses to the stroop and cold pressor tests after submaximal cycling exercise in normotensive males

Abstract

The effect of 30 min of cycling exercise at 60% VO2max on hemodynamic responses to the Stroop and cold pressor tests in 12 normotensive males was examined. Subjects were randomly assigned in a counterbalanced design to perform the stressors pre- and postexercise and served as their own controls. Cardiac output (CO), heart rate (HR), and stroke volume were measured continuously by impedance cardiography. Blood pressure was measured beat to beat using a photoplethysmographic volume transducer. Total peripheral resistance (TPR) was calculated. The systolic blood pressure response (elevation) to the Stroop test was significantly attenuated postexercise (4.2 +/- 1.4%, p < 0.05) as compared to preexercise and control (10.1 +/- 1.8%). Postexercise HR reactivity was also significantly attenuated to the Stroop test postexercise (0.3 +/- 1.7%) compared to preexercise and control (6.5 +/- 2.3%, p < 0.05). Hemodynamic variables among treatment groups, with the possible exception of HR, appeared to be unaffected during the cold pressor postexercise. Neither central (i.e., CO) nor peripheral (i.e., TPR) responses appeared to be solely responsible for the attenuated blood pressure response to the Stroop stressor.