ERYTHROPOIETIN RESPONSE TO ALTITUDE NOT ASSOCIATED WITH HEMOGLOBIN CHANGES IN TRAINED ATHLETES
Friedmann, B., Frese, F., Menold, E., Kauper, F., Jost, J., & Bartsch, P. (2005). Individual variation in the erythropoietic response to altitude training in elite junior swimmers. British Journal of Sports Medicine, 39(3), 148-153.
Interindividual variations in sea level performance after altitude training have been attributed, at least in part, to an interindividual variability in hypoxia induced erythropoiesis. This study examined whether the variability in the increase in total hemoglobin mass after training at moderate altitude could be predicted by the erythropoietin response after four hours of exposure to normobaric hypoxia at an ambient PO2 corresponding to the training altitude.
Erythropoietin levels were measured in elite junior swimmers (N = 16) before and after four hours of exposure to normobaric hypoxia (~2,500 m simulation) as well as repeatedly during three-weeks of altitude training at 2,100–2,300 m. Before and after the altitude training, total hemoglobin mass and performance in a stepwise incremental swimming test were determined.
Erythropoietin increased (interindividual variation was considerable and ranged between 10–185%) after the four-hour exposure to normobaric conditions and was significantly correlated with the acute erythropoietin increase during altitude training but not with the change in total hemoglobin mass (significant increase of ~6% on average). The change in sea level performance after altitude training was not related to the change in total hemoglobin mass.
Implication. This study confirmed the wide interindividual variability in erythropoietic response to altitude training in elite swimmers. The erythropoietin response to acute altitude exposure does not identify those athletes who respond to altitude training with an increase in total hemoglobin mass. There does not appear to be an association between increased erythropoietin and total hemoglobin in athletes.
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