'Interoception' of heart rate, blood pressure, and myocardial metabolism during ergometric work load in healthy young subjects.

In a laboratory experiment intensities of 25, 50, and 75% of the individual range of a cardiovascular parameter (heart rate, blood pressure, and Robinson-index as an index of myocardial metabolism) were demonstrated during bicycle ergometer testing with healthy young subjects. In a subsequent phase they had to reproduce the same value of the parameter in question by regulating the physical work load of the ergometer. Reproduction accuracy was taken as an interoceptive index. We concluded from our data that subjects reproduced heart rate with high internal consistency but with a systematic bias. There is no linear consistency in blood pressure reproduction, and a moderate one in the reproduction of the index of myocardial metabolism. The physiological processes, upon which the interoception and reproduction is based, remain a question of further research.