# Erythrocyte Phospholipid Fatty Acid Profile in High-Level Endurance Runners
## 4 Discussion  
The aim of our study was to determine the erythrocyte profile of a group of high-level endurance runners and observe the differences compared to a control group of individuals with low physical activity. Physical exercise and nutrition are two variables that modify the composition and function of the erythrocyte membrane [11]. Different FA compositions have been documented in the erythrocyte membrane in athletes from various sports as a result of chronic training, the relationship between the type of sport and the specificity of its training, and the characteristics of its competitions [37]. PUFAs are part of the erythrocyte membrane and regulate its fluidity and plasticity [38]. The function of \(\omega\)-3 and \(\omega\)-6 PUFAs in the body differs as both compete for the same enzymatic pathways and their incorporation into the cell membrane. In the \(\omega\)-6 family, AA is a precursor of proinflammatory eicosanoids, while in the \(\omega\)-3 family, EPA and DHA promote the production of resolvins and protectins with anti-inflammatory effects [39]. There were no significant differences in the concentrations of different \(\omega\)-6 PUFAs between EG and CG. However, both groups reported slightly elevated AA levels compared to reference indices. These slightly elevated AA values seem to be a consequence of an \(\omega\)-3 PUFA deficiency. Various studies have reported elevated AA levels in groups of athletes from different specialties and control groups with low \(\omega\)-3 concentrations [20,21,37]. In our study, both ER and CG presented a deficiency in the \(\omega\)-3 index with values significantly below 8%. As \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Parameters** & **Ranges** & **EG (n = 63)** & **CG (n = 22)** & \(p\)** & **ES** \\ \hline Total saturated fatty acids & 34–45 & 44.04 \(\pm\) 3.33 & 42.06 \(\pm\) 1.29 & 0.045 & 0.46 \\ Total polyunsaturated fatty acids & 30–43 & 38.21 \(\pm\) 3.23 & 38.96 \(\pm\) 1.03 & 0.725 & 0.11 \\ Total monounsaturated fatty acids & 15–23 & 17.21 \(\pm\) 1.20 & 11.93 \(\pm\) 0.59 & 0.004 & 0.62 \\ Saturation index & 1.7–2 & 2.70 \(\pm\) 0.45 & 2.21 \(\pm\) 1.48 & 0.281 & 0.26 \\ Desaturase 9 & - & 1.22 \(\pm\) 0.85 & 0.70 \(\pm\) 0.06 & 0.173 & 0.31 \\ \(\omega\)-3 desaturase & - & 2.15 \(\pm\) 0.97 & 3.65 \(\pm\) 1.12 & 0.039 & 0.42 \\ Elongase & - & 0.86 \(\pm\) 0.76 & 0.88 \(\pm\) 0.75 & 0.518 & 0.14 \\ \hline \hline \end{tabular}
\begin{tabular}{c c c c c} \hline \hline
**EG: endurance group; CG: control group; ES: effect size.**  
\end{table} 
Table 4: Difference in erythrocyte membrane in total fatty acids (%) and enzymes in endurance runners and controls. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Parameters** & **Ranges** & **EG (n = 63)** & **CG (n = 22)** & \(p\)** & **ES** \\ \hline Palmitic Acid. C16:0 & 17–27 & 24.52 \(\pm\) 2.08 & 18.34 \(\pm\) 0.85 & 0.231 & 0.27 \\ Stearic Acid. C18:0 & 13–20 & 20.22 \(\pm\) 1.78 & 16.24 \(\pm\) 0.92 & 0.008 & 0.58 \\ Oleic Acid C18:1 & 9–18 & 17.39 \(\pm\) 1.21 & 11.93 \(\pm\) 0.59 & 0.005 & 0.62 \\ Linoleic Acid C18.2 & 9–16 & 12.12 \(\pm\) 1.77 & 10.62 \(\pm\) 1.18 & 0.361 & 0.19 \\ Calend Acid C18:3.6 & - & 0.68 \(\pm\) 0.33 & 0.12 \(\pm\) 0.23 & 0.037 & 0.55 \\ Alpha Linoleic Acid C18:3.3 & - & 0.84 \(\pm\) 0.34 & 0.47 \(\pm\) 0.04 & 0.158 & 0.27 \\ Arachidonic Acid C20:4.6 & 13–17 & 18.05 \(\pm\) 2.21 & 18.81 \(\pm\) 0.92 & 0.742 & 0.15 \\ Eicosanpentaenoic Acid C20:5 & 0.5–0.9 & 1.26 \(\pm\) 0.70 & 0.73 \(\pm\) 0.28 & 0.019 & 0.51 \\ Docosapentaenoic Acid C22:5 & - & 1.98 \(\pm\) 0.76 & 1.39 \(\pm\) 0.45 & 0.022 & 0.48 \\ Docosabexenoic Acid C22:6 & 5–7 & 4.26 \(\pm\) 1.38 & 5.08 \(\pm\) 1.44 & 0.036 & 0.43 \\ \(\omega\)-3 index & \(>\)8\% & 6.06 \(\pm\) 1.09 & 5.81 \(\pm\) 1.89 & 0.476 & 0.22 \\ \(\omega\)-6/\(\omega\)-3 ratio & 3.5–5.5 & 4.24 \(\pm\) 0.80 & 4.29 \(\pm\) 1.09 & 0.581 & 0.17 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Difference in erythrocyte membrane fatty acids (%) in endurance runners and the control group.