## 3 Results
### Lipids Levels and Race-Related Trends
#### 3.2.2 Ceramides, DAG and SM Species  
The specific DAG and SM ceramide species at baseline, post and 24 h after the race are shown by heatmaps that provide intuitive visualization of the data table. Each colored cell on the map corresponds to a concentration value in the data file, with samples in rows and compound in columns (supplemental data). Trends of DAG classes at baseline and after the race are reported in Figure 2. The greatest changes were attributed to the DAG 36:3 that decreased significantly post-race (25.56 \(\pm\) 10.6 basal vs. 14.89 \(\pm\) 8.14 post-race \(p\) = 0.01; 22.44 \(\pm\) 8.14 24 h \(\mu\)mol/L). The other DAG species followed the same pattern but did not significantly change: DAG 32:0 (1.06 \(\pm\) 0.26; 2.32 \(\pm\) 4.6; 1.21 \(\pm\) 0.71 \(\mu\)mol/L, baseline, post-race, 24 h, respectively); 32:1 (2.07 \(\pm\) 0.71; 1.64 \(\pm\) 0.94; 2.24 \(\pm\) 1.62 \(\mu\)mol/L); 34:1 (8.22 \(\pm\) 2.68; 5.85 \(\pm\) 3.32; 8.66 \(\pm\) 4.54 \(\mu\)mol/L); 34:2 (12.1 \(\pm\) 4.85; 8.45 \(\pm\) 4.76; 12.76 \(\pm\) 9.39 \(\mu\)mol/L) and 36:4 (4.24 \(\pm\) 4.13; 2.92 \(\pm\) 2.04; 4.24 \(\pm\) 3.95 \(\mu\)mol/L) (Figure 2). \begin{table}
\begin{tabular}{c c} \hline \hline
**Anthropometric Measurement** & **Runners** \\  & **N (13)** \\ \hline Age (years) & 47 \(\pm\) 6 \\ \hline Gender (M/F) & 7/6 \\ \hline Height (cm) & 171.6 \(\pm\) 2 \\ \hline Weight (kg) & 67.5 \(\pm\) 2.2 \\ \hline BMI (kg/m\({}^{2}\)) & 21.6 \(\pm\) 0.7 \\ \hline WAIST (cm) & 78.2 \(\pm\) 3.1 \\ \hline PAS (mmHg) & 128.3 \(\pm\) 5.2 \\ \hline PAD (mmHg) & 72.16 \(\pm\) 2.3 \\ \hline FFM (kg) & 55.6 \(\pm\) 3.6 \\ \hline FAT\% (kg) & 11.54 \(\pm\) 1.5 \\ \hline
**Physical activity** & \\ \hline Day/week of training & 4 \(\pm\) 0.3 \\ \hline Km/week & 50.1 \(\pm\) 4.7 \\ \hline Years of training & 6 \(\pm\) 1 \\ \hline Half-marathon race finish time (min) & 105.2 \(\pm\) 3.7 \\ \hline \hline \end{tabular} Abbreviations: BMI: body mass index, PAS: systolic arterial pressure, PAD: diastolic arterial pressure, FFM: free fat mass.  
\end{table} 
Table 1: Anthropometric measurement of runners and physical activity. Trends of ceramide species at baseline and after the race are reported in Figure 3. Ceramide species containing long chain fatty acids (18:1/16:0; 18:1/18:0) transiently increased after the race, to significantly decrease at 24 h (0.16 \(\pm\) 0.06; 0.20 \(\pm\) 0.05; 0.18 \(\pm\) 0.04 \(\upmu\)mol/L, baseline, post-race, 24 h, respectively); (0.18 \(\pm\) 0.07; 0.18 \(\pm\) 0.03; 0.16 \(\pm\) 0.03 \(\upmu\)mol/L) (Figure 3). Instead, ceramides containing very long chain fatty acids, i.e., 18:1/25:0; 18:1/26:0; 18:1/22:0; 18:1/22:0; 18:1/24:1; 18:1/24:0; 18:0/24:0 significantly decreased after the race and at 24 h when compared to baseline (0.82 \(\pm\) 0.21; 0.55 \(\pm\) 0.13; 0.62 \(\pm\) 0.15 \(\upmu\)mol/L, baseline, post-race and 24 h, respectively); (0.16 \(\pm\) 0.05; 0.11 \(\pm\) 0.03; 0.13 \(\pm\) 0.03 \(\upmu\)mol/L); (1.52 \(\pm\) 0.35; 1.91 \(\pm\) 0.50; 1.46 \(\pm\) 0.43 \(\upmu\)mol/L); (3.29 \(\pm\) 0.91; 2.36 \(\pm\) 0.60; 2.61 \(\pm\) 0.38 \(\upmu\)mol/L); (5.56 \(\pm\) 1.4; 1.46 \(\pm\) 0.43; 4.35 \(\pm\) 0.95 \(\upmu\)mol/L) and (0.17 \(\pm\) 0.05; 0.12 \(\pm\) 0.04; 0.13 \(\pm\) 0.38 \(\upmu\)mol/L), Figure 3. SM did not significantly change. Figure 1: Bar chart reporting mean and SD of total ceramides, total DAG and SM (panel **A**, **B** and **C**, respectively) at baseline, post and 24 h after the race. Figure 2: Bar chart reporting the trend of DAG classes as mean and SD at baseline, post and 24 h after the race. Cytokines and chemokines at baseline and after the race are reported in Figure 4. IL-6 and fractalkine CX3 CL1 significantly changed soon after the race, decreasing towards baseline values after 24 h (Figure 4A,B). TNF\(\alpha\) had the same trend but the increment after the race was not significant (Figure 4C). VEGF-A tended to decrease after the race (Figure 4D), but these changes were not significant when compared to baseline.