ABC | Volume 111, Nº6, December 2018

Original Article Silva et al Cardiac and vascular features in athletes Arq Bras Cardiol. 2018; 111(6):772-781 Table 6 – Pearson linear correlation coefficients between training parameters and echocardiographic variables (RG = 24) VO 2 max (mL.kg -1 .min -1 ) VCO 2 max (mL.kg -1 .min -1 ) Pulmonary ventilation (L.min -1 ) Duration of strength training (years) Weekly duration of training (days) Daily duration of training (min/day) Interventricular septum thickness (mm) –0.640* 0.362 0.303 –0.630* 0.150 0.136 Posterior ventricular wall thickness (mm) 0.001 –0.016 0.209 0.260 –0.139 0.032 LV mass (g) –0.140 –0.137 –0.015 –0.110 –0.248 –0.100 Resting heart rate (bpm) –0.650* –0.550 –0.414 –0.659* –0.163 –0.244 Baseline SBP (mmHg) 0.177 0.311 0.341 –0.074 –0.023 –0.212 Baseline DBP (mmHg) 0.183 0.279 0.258 0.701 0.254 –0.101 RG: long-distance runners group; LV: left ventricle; SBP: systolic blood pressure; DBP: diastolic blood pressure; VO 2 : oxygen uptake, VCO 2 : carbon dioxide production. Significance level * p < 0.05. Table 7 – Pearson linear correlation coefficients between training parameters and brachial artery flow-mediated dilation measurements Squat (kg) Bench press (kg) Deadlift (kg) VO 2 max (mL. kg -1 .min -1 ) Resting heart rate (bpm) Duration of strength training (years) Weekly duration of training (days) Daily duration of training (min/ day) PG RG PG RG PG RG PG RG PG RG PG RG PG RG PG RG FMD (%) 0.710 † 0.351 0.242 0.165 0.654 † –0.383 0.073 –0.349 0.489 –0.107 0.688* 0.165 0.491 –0.123 0.770 † –0.079 PG: powerlifters group; RG: long-distance runners group; FMD: flow-mediated dilation. Significance level † p < 0.001, * p < 0.05. comparing individuals of different body sizes. BSA is affected by fat mass, and fat mass is neither correlated with nor predicts LV mass. 19 An alternative approach is to adjust echocardiographic parameters for leanmass. However, accurate measurements are not widely available and substitute methods such as skin-fold thickness measurements are relatively inaccurate. 20,21 Diastolic function assessment in the study revealed consistently normal values in long-distance runners. 22 In contrast, lower LA volume and transmitral A-wave velocity measures were found in powerlifters although these values were within normal limits. The difference of LA volume measures between both groups was ~22%, and it was even more pronounced after adjustment for BSA (~40%). D’Andrea et al., 23 and coworkers have assessed LA volume and BSA-indexed LA volume in 350 endurance athletes and 245 strength athletes. 23 For BSA-indexed measures, these authors defined values between 29 and 33 mL/m 2 as mild LA enlargement and values greater than 33 mL/m 2 as moderate LA enlargement. Thus, our results were all below the cutoff values set in D'Andrea et al., 23 As for LV systolic function assessed through estimates of ejection fraction and ejection fraction calculated by Simpson's rule, the echocardiographic assessment showed values within the normal range in all cases. Blood pressure The association of aerobic training with lower resting blood pressure is well established. 24,25 But a growing body of evidence shows that strength training can have a similar effect on blood pressure, 26 though there is not yet a consensus in the literature. 27 However, high-intensity strength training has been reported to negatively affect blood pressure. A meta‑analysis showed that training modalities that basically consist of strength training (powerlifting , bodybuilding, and Olympic weightlifting) are associated with a higher risk of high blood pressure with mean SBP of 131.3 ± 5.3 mmHg and mean DBP of 77.3 ± 1.4 mmHg. 28 These values are consistent with those found in our study (SBP 130.0 ± 8.2 and DBP 82.1 ± 6.9 mmHg). Vascular function FMD measurements were similar in both powerlifters and runners. This is an interesting finding given that these two training modalities have different biomechanical and metabolic characteristics. Exercise training has been shown as an effective means for the improvement of endothelium- dependent vasodilation capacity. 29 Among high-performance athletes, long-distance runners with above average normal cardiac function show lower arterial stiffness, lower oxidative stress, and increased endothelium-dependent dilation 30 capacity when compared to sedentary individuals of the same age. 31 These data suggest that outstanding cardiac performance in athletes may be associated with improved vascular function induced by aerobic exercise training. It is well known that aerobic exercise improves endothelial function by producing increased shear stress on the vessel walls during exercise. 32 Yet, it has been suggested that strength training can increase hemodynamic stress due to the mechanical compression of blood vessels during active movements together with excessive vascular tension produced during strength exercises. 7 Thus, we can speculate that high‑intensity strength training could acutely affect endothelium-dependent vasodilation and lead to permanent 778