INTERRELATION BETWEEN EXERCISE HEART RATE, POST-RUN SYSTOLIC BLOOD PRESSURE, AND MYOCARDIAL STRUCTURE IN DISTANCE RUNNERS
Tomas Venckūnas, Birutė Mažutaitienė, Arvydas Stasiulis
Baltic journal of sport & health sciences
Endurance running is an exercise practiced by athletes in many sports. Being benefi cial to health, it is also under-taken by a great number of non-athletic individuals. Rigorous endurance training frequently induces symmetric (i. e. both ventricular chamber dilation and wall thickening) myocardial hypertrophy, which is a physiological adapta-tion. Although distance running is a sport associated with haemodynamic volume rather than pressure overload, in addition to enlarged cardiac output,
... lic arterial blood pressure also considerably increases during running. The extent of the cardiac hypertrophy was shown to be correlated with peak blood pressure measured during laboratory exercise. However, the predominant type of myocardial hypertrophy (the ratio between the myocardial wall thickness and chamber size) in endurance runners remains contradictory, and the majority of the responsible factors are still to be determined. The aim of this study was to determine possible correlations between post-run systolic blood pressure and myocardial hypertrophy in endurance runners.Standard transthoracic two-dimensional M-mode echocardiography was performed in white adult male distance runners (n = 49) of national level within four weeks of treadmill testing, which was a non-continuous incremental exercise test employed for the determination of the heart rate as well as post-exertional systolic blood pressure re-sponse. Runners' training volume (evaluated as the average number of hours per week spent training averaged over the past four weeks) correlated (p < 0.05) positively with the left ventricular (LV) wall thickness but not with the cavity size or LV mass (p > 0.05). Training volume also positively correlated with systolic blood pressure response to exercise (p < 0.05), but negatively with submaximal exercise heart rate (p < 0.01). Post-run systolic blood pressure correlated positively with LV wall thickness and LV concentricity (namely, the ratio between the myocardial wall thick-ness and chamber size) (p < 0.05), but no signifi cant correlation of any of the LV size parameters with resting heart rate, blood pressure, or systolic blood pressure in 2 to 4 min during the recovery period was revealed. Submaximal and maximal heart rate correlated signifi cantly and negatively with LV wall thickness, LV mass, and systolic blood pressure measured immediately after running (p < 0.05).Training volume and post-run systolic blood pressure have been found to correlate positively with LV wall thickness and concentricity in white adult male distance runners. Negative correlation of exercise heart rate has been found with the post-exercise systolic blood pressure, LV wall thickness, and LV mass.