Changes in plasma volume and red cell formation after a marathon competition.
The purpose of this study was to investigate middle-term influences of a marathon race on plasma volume (PV) and red cell production. We performed the following measurements in the blood of 15 male athletes: haemoglobin ([Hb]), haematocrit (Hct), plasma protein concentration ([Prot]), plasma osmolality, sodium concentration ([Na+]), potassium concentration ([K+]), aldosterone concentration ([Aldo]), haptoglobin concentration ([Hpto]), and the reticulocyte count, as well as the calculation of relative changes in PV, 3 days before and on 3-consecutive days after a marathon race. By the 2nd day of recovery PV had increased by 16%. Plasma osmolality and [K+] remained constant, whereas [Na+] had decreased slightly 2 days after the competition and [Aldo] tended to be elevated 1 day after the competition. [Hpto] was low before and 1 day after the competition and increased on the following days. Reticulocyte count was unaffected 1 day after the race, but increased by 106% on the 2nd day and was still elevated after 3 days. The causes for higher post-marathon plasma volumes and reticulocyte counts could be in the complex variations in hormonal regulation, which have not yet been sufficiently investigated.
Schmidt
W
W
Abteilung für Sport und Arbeitsphysiologie, Medizinische Hochschule Hannover, Federal Republic of Germany.
Maassen
N
N
Tegtbur
U
U
Braumann
K M
KM
D000328:Adult; D000704:Analysis of Variance; D001772:Blood Cell Count; D004920:Erythropoiesis; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008297:Male; D010807:Physical Endurance; D010953:Plasma Volume; D012156:Reticulocytes / Q000166:cytology; D012420:Running
D006454:Hemoglobins