Author(s): LU, L., HE, Z.H., Institution: CHINA INSTITUTE OF SPORT SCIENCE, Country: CHINA, Abstract-ID: 651

INTRODUCTION:
This study aimed to investigate serum lipid metabolic characteristics associated with different pre-competition competitive states in elite hammer throw athletes using targeted lipidomics. Special emphasis was placed on sex-related differences in metabolic regulation, with the goal of identifying key lipid biomarkers with predictive potential for objective evaluation of pre-competition readiness.
METHODS:
A prospective longitudinal study (2023–2025) followed seven elite hammer throw athletes (four females, three males; two international-level). Resting serum samples were collected before twelve major competitions (1–7 days pre-competition in females; 1–9 days in males). Competitive states were classified as “high” or “low” based on upper-tertile relative performance. Targeted lipidomics (>1,600 lipids) was performed using LC–MS/MS. After MetaboAnalyst 6.0 preprocessing and auto-scaling, group differences were analyzed using PCA and OPLS-DA with 100 permutation tests. Differential lipids were defined as VIP > 1, p < 0.05, and Cohen’s d > 0.6. KEGG pathway enrichment analysis was conducted.
RESULTS:
A total of 1,292 lipid metabolites were identified. In female athletes (high n = 8; low n = 17), OPLS-DA showed clear separation between competitive states (R²Y = 0.994, p = 0.08; Q² = 0.228, p = 0.10), yielding 44 differential lipids (21 upregulated, 23 downregulated). TAG45:1-FA18:1 (VIP = 4.34, d = 1.17) and PG16:0-20:0 (VIP = 3.88, d = −1.58) were major contributors to group discrimination. Triglyceride profiles exhibited marked compositional remodeling, with TAG53:3-FA16:0(VIP=3.41) strongly downregulated (log₂FC = −14.86, p < 0.01, d=-1.018) and TAG52:0-FA18:0(VIP=2.14) significantly upregulated (log₂FC = 14.50, p < 0.05, d=0.978). Moreover, multiple functional phospholipids, such as PG16:0–20:0 (VIP = 3.88, d = −1.575) and PS22:1–22:6 (VIP = 3.77, d = 1.004), showed significant increases. Enriched pathways included glycerophospholipid metabolism (p = 0.055) and glycosylphosphatidylinositol-anchor biosynthesis (impact = 0.168), with phosphoethanolamine (C00350) identified as a key hub. In male athletes (high n = 9; low n = 12), the OPLS-DA model failed validation (Q² = −0.212, p = 0.79), indicating no reliable lipidomic discrimination.
CONCLUSION:
Pre-competition competitive state in elite female hammer throw athletes is closely associated with lipid metabolic flexibility, characterized by selective triglyceride remodeling and enrichment of functional phospholipids, suggesting coordinated optimization of energy supply and neuromuscular regulation. These lipidomic signatures reflect a metabolically prepared state rather than acute fatigue or depletion. In contrast, no stable lipidomic patterns were observed in male athletes, indicating alternative regulatory mechanisms. Collectively, these findings highlight the sex-specific utility of serum lipidomics as a sensitive molecular tool for monitoring pre-competition readiness in elite power-based events.