Hydration and human cardiovascular function
People undertaking prolonged vigorous exercise in the heat experience substantial bodily fluid losses due to sweating, a process termed dehydration. If these fluid losses are not replaced, endurance exercise performance may be impaired in association with significant alterations in physiological function, including marked cardiovascular strain. One of the major features of the cardiovascular strain induced by dehydration during prolonged running or cycling in the heat is the significant reductions in the amount of blood the heart pumps per beat (i.e., stroke volume) and per minute (i.e., cardiac output) and the concomitant lowering in peripheral tissue blood flow. How those responses are brought about is not as yet well understood. This project will investigate the cardiac and peripheral mechanisms underlying the reductions in stroke volume and cardiac output with dehydration during prolonged exercise in the heat.
The findings of this study will advance our understanding of human cardiovascular control during exercise and will inform how athletes could improve endurance exercise performance on the road to the Tokyo 2020 Olympic and Paralympic Games.
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Stöhr EJ, González-Alonso J, Pearson J, Low DA, Ali L, Barker H & Shave R (2011). Deyhdration reduces left ventricular filling at rest and during exercise independent of twist mechanics. J Appl Physiol 111, 891-897.
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