Varlet-Marie Emmanuelle, Brun Jean-Frédéric, Raynaud de Mauverger Eric, Fédou Christine
Institut des Biomolécules Max Mousseron (IBMM) UMR CNRS 5247, Université de Montpellier, Ecole Nationale Supérieure de Chimie de Montpellier, France.
Laboratoire de Biophysique & Bio-Analyses, Faculté de Pharmacie, Université de Montpellier, France.
Clin Hemorheol Microcirc. 2016;64(4):817-826. doi: 10.3233/CH-168042.
We investigated whether the concept of hematocrit/viscosity (h/η) ratio explains the "paradox of hematocrit in athletes", by calculating a "theoretical optimal hematocrit" (i.e., associated with the higher h/η value predicted with Quemada's equation from plasma viscosity, and erythrocyte rigidity index) before and after exercise. 14 rugby players (19-31 yr; weight 65.8-109.2 kg; height 1.7-1.96 m; BMI 21.7-33.1 kg/m2) underwent a standardized submaximal exercise session on cycloergometer corresponding to 225 kjoules over 30 min. The rheologic response to exercise was measured with the MT90 viscometer and the Myrenne aggregometer. After exercise there was an increase in whole blood viscosity (p < 0.05) and hematocrit (p < 0.005) and a decrease in h/η ratio (from 14.7±0.34 to 12.9±0.37, p < 0.005). There was an increase in viscometric RBC rigidity indexes "Tk" and "k" in 9/14 subjects. Predicted and actual h/η are fairly well correlated (preexercise r = 0.998, p < 0.001; postexercise r = 0.985 p < 0.001) but actual h/η was lower than predicted (preexercise p = 0.005; postexercise p = 0.02). This discrepancy between predicted and measured hematocrit was not correlated to dehydration or plasma viscosity but was correlated to red cell rigidity (r = 0.774, p < 0.01) and its exercise-induced change (r = 0.858, p < 0.01). This study suggests that h/η, although it is not directly correlated to parameters of exercise performance, is precisely regulated during exercise according to the classic concept of "viscoregulation", and that the prediction of the theoretical optimal values of h/η and hematocrit by models may help to interpret the actual values of these parameters. However, these models need to be more extendedly tested and improved.
我们通过计算运动前后的“理论最佳血细胞比容”（即根据血浆粘度和红细胞刚性指数，用凯马达方程预测的与较高血细胞比容/粘度（h/η）值相关的数值），研究血细胞比容/粘度（h/η）比值的概念是否能解释“运动员血细胞比容悖论”。14名橄榄球运动员（年龄19 - 31岁；体重65.8 - 109.2千克；身高1.7 - 1.96米；体重指数21.7 - 33.1千克/平方米）在自行车测力计上进行了一次标准化的亚极量运动，持续30分钟，相当于225千焦。用MT90粘度计和迈伦凝聚仪测量运动后的流变学反应。运动后全血粘度增加（p < 0.05），血细胞比容增加（p < 0.005），h/η比值降低（从14.7±0.34降至12.9±0.37，p < 0.005）。14名受试者中有9名的粘度测定红细胞刚性指数“Tk”和“k”增加。预测的和实际的h/η相当相关（运动前r = 0.998，p < 0.001；运动后r = 0.985，p < 0.001），但实际的h/η低于预测值（运动前p = 0.005；运动后p = 0.02）。预测的和测量的血细胞比容之间的这种差异与脱水或血浆粘度无关，但与红细胞刚性相关（r = 0.774，p < 0.01）及其运动诱导的变化相关（r = 0.858，p < 0.01）。本研究表明，h/η虽然与运动表现参数没有直接相关性，但在运动过程中根据“粘度调节”的经典概念受到精确调节，并且通过模型预测h/η和血细胞比容的理论最佳值可能有助于解释这些参数的实际值。然而，这些模型需要更广泛的测试和改进。
