Bei 21 hoch trainierten Radsportlern wurde die Herzfrequenzreaktion (HR) bei Belastung zu ihren Herzmaßen verglichen. Ergebnis: Die HR-Reaktion zeigte einen Deflektionspunkt (HRd)bei etwa 85 % der VO2max bei 66,7 % der Probanden (D=Gruppe, n=14) und war bei 33,3 % linear (NoD-Gruppe, n=7). Linker Ventrikelmassenindex (LVMI), linkes Atriummaß (LAD), linkes Atriummaß im Längsschnitt (LLAD) und rechtes Atriummaß im Längsschnitt (LRAD) waren in jeder Gruppe gleich. In der D-Gruppen waren linke vordere Ventrikeldicke zur Enddiastole (LPWTd) und interventrikuläre Septalwanddicke zur Enddiastole (IVSTd) signifikant höher. Das Verhältnis von früher zu später diastolischer Fließgeschwindigkeit (E/A) war in den Gruppen nicht sign. unterschiedlich. OBJECTIVES: 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 deflection point (HRd) at about 85% VO2MAX 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 significantly higher in the D group. Finally, no significant difference between groups was found with respect to the E/A. CONCLUSIONS: 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.
© Copyright 1999 British Journal of Sports Medicine. BMJ Publishing Group Ltd of the BMA. Alle Rechte vorbehalten.