Heart dimensions may influence the occurrence of the heart rate deflection point in highly trained cyclists

To determine whether the heart rate (HR) response to exercise in 21 highly trained cyclists (mean (SD) age 25 (3) years) was related to their heart dimensions. Methods—Before performing an incremental exercise test involving a ramp protocol with workload increases of 25 W/min, each subject underwent...

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Detalles Bibliográficos
Autores: Lucía Mulas, Alejandro, Carvajal, Alfredo, Boraita, Araceli, Serratosa Fernández, Luis, Hoyos, J., Chicharro, José L.
Tipo de recurso: artículo
Fecha de publicación:1999
País:España
Institución:Universidad Europea (UEM)
Repositorio:ABACUS. Repositorio de Producción Científica
Idioma:inglés
OAI Identifier:oai:abacus.universidadeuropea.com:11268/6011
Acceso en línea:http://hdl.handle.net/11268/6011
Access Level:acceso abierto
Palabra clave:Condición física
Ciclismo
Medicina deportiva
Atleta
Descripción
Sumario:To determine whether the heart rate (HR) response to exercise in 21 highly trained cyclists (mean (SD) age 25 (3) years) was related to their heart dimensions. Methods—Before performing an incremental exercise test involving a ramp protocol with workload increases of 25 W/min, each subject underwent echocardiographic evaluation of the following variables: left ventricular end diastolic internal diameter (LVIDd), left ventricular posterior wall thickness at end diastole (LVPWTd), interventricular septal wall thickness at end diastole (IVSTd), left ventricular mass index (LVMI), left atrial dimension (LAD), longitudinal left atrial (LLAD) and right atrial (LRAD) dimensions, and the ratio of early to late (E/A) diastolic flow velocity. Results—The HR response showed a de- flection point (HRd) at about 85% V~ O2MAX in 66.7% of subjects (D group; n = 14) and was linear in 33.3% (NoD group; n = 7). Several echocardiographic variables (LVMI, LAD, LLAD, LRAD) indicative of heart dimensions were similar in each group. However, mean LPWTd (p<0.01) and IVSTd (p<0.05) values were signifi- cantly higher in the D group. Finally, no significant diVerence between groups was found with respect to the E/A. The HR response is curvilinear during incremental exercise in a considerable number of highly trained endurance athletes—that is, top level cyclists. The departure of HR increase from linearity may predominantly occur in athletes with thicker heart walls.