# Rheological and Biochemical Properties of Blood in Rumers: A Preliminary Report
## 4 Discussion  
Physical activity induces numerous modifications in the morphological, rheological, and biochemical properties of blood. Investigating these blood properties allows us to characterise the actual extent and direction of exercise changes in runners. The results obtained in the presented study indicate that the morphological, rheological, and biochemical blood indicators did not change in the athletes. Most likely, as a result of the applied training, the bodies of trained athletes adapt their haemodynamic response to the current conditions and the tissue demand for blood flow. The selection of appropriate training loads, as well as the quick regeneration after the analysed training units, confirm the very high level of training and regeneration. Even submaximal and maximal competition efforts did not result in a significant disturbance in the biochemical or morphological blood parameters. This only confirms that outstanding athletes, at a high sporting level, present a much higher adaptability to physical effort and display enormous regeneration efficiency. [PERSON] [14] conducted one of the first studies to explore the influence of regular physical activity on blood rheological properties. Blood samples were collected from 14 training individuals, and a comparison with a control group of 12 sedentary males was performed. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Indicator** & **Before** & **After** & \(p\)**-Value for Student’s \(t\)-Test** \\ \hline Iron, \(\mu\)mol/L & 17.425 \(\pm\) 7.826 & 16.792 \(\pm\) 4.591 & \(>\)0.05 \\ Transferrin, mg/dL & 261.917 \(\pm\) 30.315 & 268.833 \(\pm\) 33.499 & \(>\)0.05 \\ Ferritin, ng/mL & 57.917 \(\pm\) 28.916 & 59.017 \(\pm\) 28.477 & \(>\)0.05 \\ CK-MB activity, U/L & 18.700 \(\pm\) 4.506 & 19.158 \(\pm\) 4.937 & \(>\)0.05 \\ CK-MB mass, ng/mL & 5.341 \(\pm\) 2.960 & 6.661 \(\pm\) 4.406 & \(>\)0.05 \\ Erythrooietin, ml/mL & 9.938 \(\pm\) 3.703 & 9.758 \(\pm\) 3.740 & \(>\)0.05 \\ hs-CRP, mg/L & 0.331 \(\pm\) 0.177 & 0.563 \(\pm\) 0.784 & \(>\)0.05 \\ \hline \hline \end{tabular}  
* CK-MB—creatine kinase MB isoenzyme; hs-CRF—high-sensitivity C-reactive protein.  
\end{table} 
Table 4: Selected biochemical parameters (mean values \(\pm\) standard deviation) in the examined runners before and after the effort. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Indicator** & **Before** & **After** & \(p\)**-Value for Student’s \(t\)-Test** \\ \hline EI at 0.30 Pa & 0.051 \(\pm\) 0.006 & 0.050 \(\pm\) 0.006 & \(>\)0.05 \\ EI at 0.58 Pa & 0.148 \(\pm\) 0.011 & 0.147 \(\pm\) 0.011 & \(>\)0.05 \\ EI at 1.13 Pa & 0.233 \(\pm\) 0.011 & 0.232 \(\pm\) 0.012 & \(>\)0.05 \\ EI at 2.19 Pa & 0.339 \(\pm\) 0.009 & 0.337 \(\pm\) 0.012 & \(>\)0.05 \\ EI at 4.24 Pa & 0.434 \(\pm\) 0.009 & 0.434 \(\pm\) 0.011 & \(>\)0.05 \\ EI at 8.23 Pa & 0.512 \(\pm\) 0.008 & 0.512 \(\pm\) 0.011 & \(>\)0.05 \\ EI at 15.95 Pa & 0.563 \(\pm\) 0.007 & 0.563 \(\pm\) 0.008 & \(>\)0.05 \\ EI at 30.94 Pa & 0.599 \(\pm\) 0.008 & 0.599 \(\pm\) 0.007 & \(>\)0.05 \\ EI at 60.00 Pa & 0.629 \(\pm\) 0.007 & 0.628 \(\pm\) 0.005 & \(>\)0.05 \\ AMP, au & 35.675 \(\pm\) 2.530 & 36.440 \(\pm\) 2.665 & \(>\)0.05 \\ AI, \% & 48.296 \(\pm\) 8.058 & 47.775 \(\pm\) 8.750 & \(>\)0.05 \\ T1/2, s & 4.533 \(\pm\) 1.566 & 4.689 \(\pm\) 1.606 & \(>\)0.05 \\ FIBR, g/L & 2.382 \(\pm\) 0.257 & 2.595 \(\pm\) 0.302 & 0.024 * \\ \hline \hline \end{tabular}  
* EI—elongation index; AMP—amplitude and total extent of aggregation; AI—aggregation index; T1/2—aggregation half-life; FIBR—fibrinogen;* significant difference (\(p\) \(<\) 0.05).  
\end{table} 
Table 3: Red blood cell rheological parameters (mean values \(\pm\) standard deviation) in the examined runners before and after the effort. The author investigated plasma viscosity and the degree of erythrocyte deformability. In the experimental group, plasma viscosity was reduced and erythrocyte deformability was improved. After 3 months of training, the control group presented similar blood rheological parameters to the group of athletes.