RESUMO
To determine the effects of intense training on aortic pulse wave variables and hemodynamic parameters at baseline and at recovery from maximal exercise testing (MaxET) in triathletes compared with sedentary individuals. In this prospective and experimental study, 21 triathletes and 21 sedentary individuals were recruited and evaluated prior and two minutes after the MaxET using the Mobil-O-Graph®, which estimates the aortic pulse wave from the brachial artery pressure. The augmentation index (AIx@75) was lower in triathletes after the MaxET compared to control group (16.34 ± 5.95 vs. 23.5 ± 8.53%, p = 0.001), while the pulse wave velocity (PWV) was similar between groups. The heart rate was significantly lower at baseline and after MaxET in triathletes group (55.70 ± 8.95 bpm 91.49 ± 11.39 bpm) compared with control group (62.11 ± 6.70 bpm; 102.08 ± 10.85 bpm). The stroke volume was significantly higher at baseline (96.08 ± 13.96 ml; 86.17 ± 11.24 ml) and after MaxET in triathletes group (69.15 ± 6.51 ml, 58.38 ± 6.99 ml) compared with control group. Triathetes show lower value of AIx@75 after MaxET in comparison with the control group. AIx@75, in addition to being an indirect measure of arterial stiffness, is also a measure of left ventricular afterload. Thus, the lower AIx@75 in triathletes may be due to their lower left ventricular afterload, lower myocardial oxygen demand, and greater coronary perfusion than sedentary individuals. The hemodynamic changes observed in triathletes at rest and during an acute exercise bout are distinctive characteristics of aerobic physical training.
