Relationships Between Hematological Variables and Bone Metabolism in Elite Female Trail Runners

Background: This study investigated the relationships between hematological and bone metabolism variables in 35 elite female trail runners, focusing on identifying key hematological correlates of bone health. Methods: Forty-four hematological variables, including biochemical, hormonal, metabolic, liver enzyme, and iron profiles, as well as complete blood count and platelet indices, were analyzed. Bone mineral density (BMD) and bone mineral content (BMC) were assessed at multiple skeletal regions via dual-energy X-ray absorptiometry (DXA). A cross-sectional design was employed, utilizing descriptive statistics, correlation analyses, and multiple linear regression to analyze the associations between hematological markers and BMC and BMD. Results: Significant but moderate associations were identified: magnesium consistently emerged as a negatively associated factor, particularly associated with BMC and BMD in the lumbar spine (L1–L4) and whole-body, potentially reflecting hypothesized mineral mobilization during chronic physical stress. Follicle-stimulating hormone showed positive associations with BMD, suggesting a potential protective association in bone turnover regulation. Additionally, calcium and thyroid hormones were linked to regional bone properties, highlighting site-specific skeletal vulnerabilities. Conclusions: These findings suggest a complex interplay between mineral homeostasis and hormonal balance that may be related to skeletal integrity in elite female trail runners. This work provides a foundation for developing evidence-based guidelines to support the health and performance of female endurance athletes. Further research is warranted to confirm these results through longitudinal evaluations.