P7.03 MARATHON RUNNERS HAVE INCREASED AORTIC STIFFNESS

Abstract

Purpose: It is well known that regular moderate aerobic exercise has a beneficial effect on cardiovascular risk, although the impact of long-term intense aerobic training has not been defined. Aortic stiffness and wave reflections are independent predictors of cardiovascular risk. In this study we assessed the chronic effect of intense endurance training on the elastic properties of the large arteries. Methods: The study population consisted of 49 healthy (mean age: 37±5yrs), regularly trained (5.8±3.6hours/week for 11.6±9.1 years) marathon runners (mean age: 38±9yrs) and 46 controls matched for classical risk factors. Aortic stiffness was evaluated with carotid-femoral pulse wave velocity (PWV) and wave reflections with augmentation index (AIx) of the aortic pressure waveform. Results: Marathon runners had significantly higher systolic pressure (aortic and brachial) (113±15 vs. 102±11, P<0.01 and 126±15 vs. 115±12, P<0.01, respectively) compared to controls. Aortic and brachial diastolic pressure- (79±10 vs.72±9, P<0.01 and 78±10 vs.71±9, P<0.01, respectively) and mean pressure (94±12 vs. 86±10, P=0.01) were also increased compared to controls. PWV was increased in athletes compared to controls (6.9±1 vs. 6.3±1, P<0.01), indicating increased aortic stiffness. AIx corrected for heart rate (8.2±12.2 vs. 10.3±9.5, P=NS) did not differ among the two groups. Years of exercise were associated with aortic pulse pressure (r=0.304, P=0.045) and AIx (r=0.388, P=0.009) in athletes. Conclusions: Marathon runners have increased aortic stiffness, as welll as central and peripheral haemodynamic parameters. These findings could contribute to precisely assess cardiovascular risk in marathon runners focusing on the proper training volumes, frequency and duration.