Effects of Exercise and Training on Blood Rheology

The effects of exercise on the rheological properties of blood have not received much research attention. Recent, limited evidence indicates that the viscosities of whole blood and plasma increase in response to a variety of exercise protocols. The increase in whole blood viscosity is mainly attributed to an increase in haematocrit and plasma viscosity, whereas the deformability and aggregability of red blood cells remain unaltered. The increases in plasma viscosity and haematocrit have been ascribed to exercise-induced haemoconcentration as a result of fluid transfer from the blood to the interstitial spaces.