Cardiovascular response of trained and untrained old men to mental challenge

The cardiovascular response to mental challenge of trained and untrained older men was examined. Blood pressure, heart rate, stroke volume, cardiac output, total peripheral resistance (TPR), rate pressure product, and cardiac contractility of 10 aerobically trained (trained) and 10 untrained (untrained) older men during and recovering from the Stroop task were compared. Fitness was assessed by online, open-circuit spirometry using a bicycle ergometer. Trained compared with untrained men showed significantly lower absolute heart rate during and recovering from the Stroop and greater left ventricular ejection time recovering from Stroop. Delta TPR scores were greater for Trained during and recovering from the Stroop, whereas delta systolic blood pressure was greater recovering from Stroop. These results indicate that although aerobically trained men possessed lower absolute heart rate their change in TPR and systolic blood pressure during mental challenge was significantly greater than that of untrained older men. The greater vascular response of the trained to mental challenge may reflect greater sensitivity to alpha-adrenergic stimulation.