Abstract

The role of heart rate (fH) in the perception of exertion (RPE) during short term progressive and prolonged (1 h) exercise has been studied in healthy malesubjects by observing the effects of experimentally changing fH, using intravenous injections of either atropine or practolol to modify the influence of the autonomic system. In short term exercise the results showed that independently of the large changes produced in fH for a given oxygen intake, the subjects rated their exertion in accordance with the relative work performed (i. e. V02max) in all experiments with and without drug administration. In prolonged exercise the association of RPE and V02max was less clear. After 10 min of prolonged exercise at the same V02 the RPE scores were lower than those observed in the progressive work tests and with atropinisation and beta-blocade RPE tended to rise during the exercise to reach a maximum value at the 60th min though V02 remained unchanged. It was concluded that heart rate per se has little influence on RPE and is not an important factor underlying the perception of effort. Nor can it be used to explain the close association between RPE and relative work load found in short term exercise. Verf.-Referat (gekuerzt)