Nutritional and metabolic determinants of blood rheology differ between trained and sedentary individuals

Body composition and nutrition have been reported to be correlated with blood rheology. However, in sedentary and in physically active individuals these relationships seem to be not exactly similar. This study investigated whether exercise training status influences these relationships. 32 athletes (ATH) (age: 25 ± 0.7 yr; body mass index (BMI): 23.75 ± 0.23 kg/m2) were compared to 21 sedentary subjects (SED) (age: 45.19 ± 2.90; BMI = 33.41 ± 1.33) with nutritional assessment (autoquestionnaire), bioelectrical impedancemetry, viscometry at high shear rate (MT90) and Myrenne aggregometer. Subjects differ according to age, weight and adiposity parameters. Their eating behavior is different: ATH eat a higher percentage of protein (p < 0.005), a lower percentage of lipid (p < 0.05), and a higher total amount of carbohydrate (+31% p < 0.02). Their viscosity factors are similar except plasma viscosity which is higher in SED than ATH (1.51 ± 0.03 vs 1.43 ± 0.02 mPa.s, p < 0.05). In both ATH and SED, abdominal obesity (waist-to-hip ratio or WHR) is associated with impairments in blood rheology, but not exactly the same. In ATH, WHR is associated with an increase in hematocrit (r = 0.647; p = 0.009), plasma viscosity (r = 0.723; p = 0.002), and caloric (and CHO) intake moderately increase RBC rigidity (r = 0.5405; p = 0.0251) and aggregability (r = 0.3366 p = 0.0596). In SED the picture is different, adiposity increases hematocrit (r = 0.460; p = 0.048), abdominal fatness increases blood viscosity independent of hematocrit, and CHO intake is associated with lower RBC aggregability (r = -0.493; p = 0.0319).