Influence of ergometer exercise on aortic pressure-diameter relationship in healthy men.

In order to investigate the change of the aortic pressure-diameter relationship during exercise, M-mode echograms and/or two-dimensional echograms of the aortic root and of the abdominal aorta were taken before and during supine ergometer exercise in 15 healthy men. The difference of the angle of the ultrasonic beam to the aorta between before and during exercise was too small to influence the measured values. The exercise, which elevated heart rate to 100 beats/min, caused a shift of the pressure-diameter relationship curve of the aortic root to a lower diameter (on an average, end-systolic diameter: from 3.1 to 2.9 cm, p less than 0.001; end-diastolic: from 2.9 to 2.7 cm, p less than 0.001). This was also seen in the abdominal aorta. Stroke volume showed no change during exercise. Total peripheral vascular resistance decreased. Central aortic volume decreased. In conclusion, exercise induces active constriction of aorta with dilatation of arterioles. This might be beneficial to push the blood into the peripheral tissues.