Different Responses In Lipid Biomarkers Between Starters And Non-starters Of Soccer Players

Biomarkers are effective indicators of training-induced adaptations. While starters and non-starters within the same team may have experienced different training loads during a season, how this affects lipid biomarkers and C-reactive protein (CRP) is not well documented. PURPOSE: To determine differences in lipid biomarkers and CRP between starters (S) (>60% match starters) and non-starters (NS) in soccer athletes. METHODS: Player load (PL), player distance (PD), velocity load (VL), and mean heart rate (HR) of 20 Division I soccer players (21 ± 1 yr) were monitored during the 2015-16 season using wearable devices. Blood samples were collected at five time points: Preseason (PS), Week 1 (WK1), Week 4 (WK4), Week 8 (WK8), and Week 12 (WK12) to assess total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), CRP, lipoprotein A, and apolipoprotein B, along with calculating TC:HDL and non-HDL:TC. Group x time repeated measures ANOVA was used to assess lipid biomarker and training load changes, with Bonferroni post hoc tests detecting differences across time points. RESULTS: Table 1 shows biomarker values at each time point. HDL was higher in S compared to NS at WK1 (MD = 13.20, 95% CI: 5.65-20.75, p = 0.003) and WK12 (MD = 12.20, 95% CI: 4.43-19.97, p = 0.006). NS had a higher TC:HDL at WK4 (MD = 0.61, 95% CI: 0.08-1.14, p = 0.028), WK8 (0.56, 0.22-0.90, p = 0.005), and WK12 (0.81, 0.16-1.47, p = 0.021). CRP levels were higher in S than NS at WK1 (0.61, 0.01-1.21, p = 0.048) and WK12 (1.49, 0.26-2.71, p = 0.023). There were no significant differences between S and NS in the remaining lipid biomarkers across all time points (all p > 0.050). CONCLUSION: The differences in HDL, CRP, and TC:HDL between S and NS are likely linked to discrepancies in training load throughout the season. Tailoring training strategies to reflect the different training loads of S and NS may help to optimize health and performance for both groups.