Lactic acidosis, potassium, and the heart rate deflection point in professional road cyclists

The aim of this study is to determine the influence of lactic acidosis, the Bohr effect, and exercise induced hyperkalaemia on the occurrence of the heart rate deflection point (HRDP) in elite (professional) cyclists. Sixteen professional male road cyclists (mean (SD) age 26 (1) years) performed a r...

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Detalles Bibliográficos
Autores: Lucía Mulas, Alejandro, Hoyos, J., Santalla Hernández, Alfredo, Pérez Ruiz, Margarita, Carvajal, Alfredo, López Chicharro, José
Tipo de recurso: artículo
Fecha de publicación:2002
País:España
Institución:Universidad Europea (UEM)
Repositorio:ABACUS. Repositorio de Producción Científica
Idioma:inglés
OAI Identifier:oai:abacus.universidadeuropea.com:11268/5702
Acceso en línea:http://hdl.handle.net/11268/5702
Access Level:acceso abierto
Palabra clave:Condición física
Ciclismo
Medicina deportiva
Descripción
Sumario:The aim of this study is to determine the influence of lactic acidosis, the Bohr effect, and exercise induced hyperkalaemia on the occurrence of the heart rate deflection point (HRDP) in elite (professional) cyclists. Sixteen professional male road cyclists (mean (SD) age 26 (1) years) performed a ramp test on a cycle ergometer (workload increases of 5 W/12 s, averaging 25 W/min). Heart rate (HR), gas exchange parameters, and blood variables (lactate, pH, P50 of the oxyhaemoglobin dissociation curve, and K+) were measured during the tests. A HRDP was shown in 56% of subjects at about 88% of their maximal HR (HRDP group; n = 9) but was linear in the rest (No-HRDP group; n = 7). In the HRDP group, the slope of the HR-workload regression line above the HRDP correlated inversely with levels of K+ at the maximal power output (r = -0.67; p<0.05). The HRDP phenomenon is associated, at least partly, with exercise induced hyperkalaemia.