Temperature sensitivity of the human cardiac pacemaker during exercise.

Archives internationales de physiologie et de biochimie
C P Bolter, V K Kebas

Abstract

The temperature sensitivity of the human cardiac pacemaker was investigated during exhaustive exercise. From graded runs to exhaustion, we established the relationship between maximum exercise heart rate (HRmax) and rectal temperature (Tr). After warm-up periods of varying intensity and duration, four male subjects completed 4 to 6 runs each, each run performed on a separate day. For every subject there was a strong linear correlation between HRmax and Tr (r = 0.79 to 0.96). Various measures of the temperature sensitivity were: linear sensitivity, 8.8 +/- 4.3 beats min-1.degrees C-1; Q10, 1.6 +/- 0.4 and the Arrhenius constant, mu, 35.9 +/- 16.6 kJ.mol-1. At HRmax the value for linear temperature sensitivity was similar to, but the values for Q10 and mu lower than, those observed previously for intrinsic heart rate. Sympathetic influence on the cardiac pacemaker during exercise may cause this reduction, by shifting the pacemaker location to cells with a lower temperature sensitivity, or by altering a rate-limiting step determining the diastolic pacemaker potential.

References

Jun 1, 1986·The Australian Journal of Experimental Biology and Medical Science·C P BolterA K Singh
May 20, 1956·The Journal of General Physiology·O F HUTTER, W TRAUTWEIN

❮ Previous
Next ❯

Citations

Mar 11, 2020·Frontiers in Cardiovascular Medicine·Anna KontosJames Martin

❮ Previous
Next ❯

Related Concepts

Related Feeds

Cardiac Conduction System

The cardiac conduction system is a specialized tract of myocardial cells responsible for maintaining normal cardiac rhythm. Discover the latest research on the cardiac conduction system here.

Related Papers

Arquivos brasileiros de cardiologia
Valter Abrantes Pereira da SilvaRicardo Jacó de Oliveira
Medicine and Science in Sports and Exercise
Ronald L GellishVirinder K Moudgil
European Journal of Applied Physiology
Anthony J BullSharon R Rana
© 2022 Meta ULC. All rights reserved