In the present study, we investigated possible alterations in red blood cell (RBC) deformability, plasma and whole blood viscosities (WBV) and hematological parameters in response to Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) which is currently used to assess endurance performance, in female volleyball players. Eight volleyball player volunteers from Pamukkale University (mean age19,9 ± 2,2 years; mean body height 177.5 ± 1.99 cm; mean body mass index 21.66 ± 0.64 kg/m2) participated to the study. Blood samples were collected before and immediately after test. Red blood cell (RBC) deformability was determined by ektacytometer, plasma and whole blood viscosities (WBV) by a cone-plate rotational viscometer. Hematological parameters were determined using an electronic hematology analyzer. The Yo-YoIR1 applied, induced acute increments in WBV at native hematocrit (Hct) measured at a shear rate of 150 s-1 and 375 s-1, RBC deformability and WBC count. The results of the current study indicate that, the Yo-Yo IR1 test used to determine physical capacity of the player, by resulting in increments in RBC deformability contributes blood flow and thus, athletic performance of the individual.
Keywords: Yo-Yo intermittent recovery test level 1 (Yo-YoIR1); erythrocyte deformability; exercise; viscosity.