title: Effect of simulated altitude erythrocythemia in women on hemoglobin flow rate during exercise.
abstract: The effect of simulated altitude erythrocythemia on hemoglobin flow rate and maximal O2 uptake (VO2max) was determined for nine women sea-level residents. Test conditions included normoxia and normobaric hypoxia (16% O2-84% N2). Cycle tests were performed under normoxia (T1-N) and hypoxia (T1-H) at prereinfusion control and under hypoxia 48 h after a placebo infusion (T2-H) and 48 h after autologous infusion of 334 ml of erythrocytes (T3-H). Hematocrit (38.1-44.9%) and hemoglobin concentration (12.7-14.7 g.dl-1) increased from control to postreinfusion. At peak exercise, VO2max decreased from T1-N (2.40 l.min-1) to T1-H (2.15 l.min-1) then increased at T3-H (2.37 l.min-1). Maximal arterial-mixed venous O2 difference decreased from T1-N to T1-H and increased at T3-H. Cardiac output (Q), stroke volume, heart rate, and total peripheral resistance during maximal exercise were unchanged from T1-N through T3-H. Hemoglobin flow rate (Hb flow) at maximum did not change from T1-N to T1-H but increased at T3-H. When compared with submaximal values for T1-N, VO2 was unchanged at T1-H and T3-H; Q increased at T1-H and decreased at T3-H; arterial-mixed venous O2 difference decreased at T1-H and increased at T3-H; Hb flow did not change at T1-N but increased at T3-H. For young women, simulated altitude erythrocythemia increased peak Hb flow and decreased physiological altitude (227.8 m) but did not affect maximum cardiac output (Qmax).
authors: Human Energy Research Laboratory, School of Medicine, University of Pittsburgh, Pennsylvania 15261.
authors: R J
authors: RJ
authors: Robertson
authors: R
authors: R
authors: Gilcher
authors: K F
authors: KF
authors: Metz
authors: C J
authors: CJ
authors: Caspersen
authors: T G
authors: TG
authors: Allison
authors: R A
authors: RA
authors: Abbott
authors: G S
authors: GS
authors: Skrinar
authors: J R
authors: JR
authors: Krause
authors: P A
authors: PA
authors: Nixon
mesh_terms: D000328:Adult; D000531:Altitude; D001783:Blood Flow Velocity; D001804:Blood Transfusion, Autologous; D002302:Cardiac Output; D005260:Female; D006339:Heart Rate; D006801:Humans; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D005082:Physical Exertion; D011086:Polycythemia / Q000209:etiology / Q000503:physiopathology*; D013318:Stroke Volume
chemical_list: D010100:Oxygen