Hematological, inflammatory, and hypoxia-responsive adaptations to 18-day normobaric live high-train low training in elite rowers

Introduction: The Live High-Train Low (LH-TL) altitude training method may stimulate erythropoietin (EPO) and vascular endothelial growth factor (VEGF) production, contributing to hematological and physiological adaptations. This study aimed to investigate the effects of an 18-day LH-TL protocol on hematological, inflammatory, and hypoxia-responsive biomarkers in elite rowers. Methods: Thirteen national-level male rowers were assigned to a hypoxic group (H; n = 8) or a control group (C; n = 5). The H group lived in normobaric hypoxic rooms for 18 days while training in normoxia. Levels of EPO, VEGF, C-reactive protein (CRP), and creatine kinase (CK) were measured along with hematological parameters at baseline, after 6, 12, and 18 days. Results: EPO levels were higher in the hypoxic group after 18 days compared with the control group. Reticulocyte counts increased after 6 days (15.0 ± 6.2‰) and remained elevated after 18 days, indicating an early erythropoietic response. Hemoglobin showed a non-significant increasing trend, while hematocrit values were significantly higher in the hypoxic group after 18 days. RBC counts remained stable in the hypoxic group, while a slight decline was observed in the control group. VEGF concentrations did not change significantly over time or between groups, although a transient increase was observed around day 12. CRP levels increased after 6 and 18 days, indicating a transient inflammatory response without clinical signs of infection. WBC counts showed a significant group × time interaction, suggesting subtle modulation of immune function in response to LH-TL. CK levels decreased initially but increased again after 18 days, without evidence of excessive muscle damage. Conclusion: These findings indicate that the LH-TL protocol induces moderate hematological and inflammatory responses in elite rowers. LH-TL may support physiological adaptations relevant to endurance capacity; however, it also represents an additional physiological load that should be carefully monitored during training. Importantly, due to the absence of direct performance measures, the results should be interpreted in terms of physiological adaptations rather than improvements in athletic performance. Trial registration ID: NCT0626419
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Bibliographic Details
Subjects:
Notations:endurance sports biological and medical sciences
Tagging:Hämatologie
Published in:Frontiers in Physiology
Language:English
Published: 2026
Volume:17
Pages:1834329
Document types:article
Level:advanced