Failure of prolonged exercise training to increase red cell mass in humans

1996 ◽  
Vol 270 (1) ◽  
pp. H121-H126 ◽  
Author(s):  
J. K. Shoemaker ◽  
H. J. Green ◽  
J. Coates ◽  
M. Ali ◽  
S. Grant

The purpose of this study was to investigate the time-dependent effects of long-term prolonged exercise training on vascular volumes and hematological status. Training using seven untrained males [age 21.1 +/- 1.4 (SE) yr] initially consisted of cycling at 68% of peak aerobic power (VO2peak) for 2 h/day, 4-5 days/wk, for 11 wk. Absolute training intensity was increased every 3 wk. Red cell mass (RCM), obtained using 51Cr, was unchanged (P > 0.05) with training (2,142 +/- 95, 2,168 +/- 86, 2,003 +/- 112, and 2,080 +/- 116 ml at 0, 3, 6, and 11 wk, respectively) as were serum erythropoietin levels (17.1 +/- 4.3, 13.9 +/- 3.5, and 17.0 +/- 2.0 U/l at 0, 6, and 11 wk, respectively). Plasma volume measured with 125I-labeled albumin and total blood volume (TBV) were also not significantly altered. The increase in mean cell volume that occurred with training (89.7 +/- 0.95 vs. 91.0 +/- 1.0 fl, 0 vs. 6 wk, P < 0.05) was not accompanied by changes in either mean cell hemoglobin or mean cell hemoglobin concentration. Serum ferritin was reduced 73% with training (67.4 +/- 13 to 17.9 +/- 1 microgram/l, 0 vs. 11 wk, P < 0.05). Total hemoglobin (HbTot) calculated as the product of hemoglobin concentration and TBV was unaltered (P > 0.05) at both 6 and 11 wk of training. The 15% increase in VO2peak (3.39 +/- 0.16 to 3.87 +/- 0.14 l/min, 0 vs. 11 wk, P < 0.05) with training occurred despite a failure of training to change TBV, RCM, or HbTot.

2003 ◽  
Vol 13 (6) ◽  
pp. 544-550 ◽  
Author(s):  
Rilvani C. Gonçalves ◽  
Carlos Alberto Buschpigell ◽  
Antonio Augusto Lopes

In the Eisenmenger syndrome, indirect estimation of blood volumes may provide quite inaccurate information when seeking to define therapeutic strategies. With this in mind, we analyzed directly the red cell mass, plasma volume, and total blood volume in patients with pulmonary hypertension associated with congenital cardiac defects and erythrocytosis, comparing the results with the respective estimated volumes, and examining the changes induced by therapeutic hemodilution.Thus, we studied 17 patients with the Eisenmenger syndrome, aged from 15 to 53 years, in the basal condition, studying 12 of them both before and after hemodilution. We also investigated five individuals with minimal cardiac lesions, aged from 14 to 42 years, as controls. Red cell mass and plasma volumes were measured using [51 chromium]-sodium chromate and [131iodine]-albumin respectively. Hemodilution was planned so as to exchange 10% of the total blood volume, using 40,000 molecular weight dextran simultaneously to replace the removed volume. The mean values of the red cell mass, plasma volume and total blood volume as assessed by radionuclide techniques were 32%, 31% and 32% higher than the respective volumes as estimated using empirical mathematical formulas (p < 0.002). The measured total blood volume was also 19% higher in the patients compared with controls. Following a period of 5 days after hemodilution, we noted a 13% reduction in red cell mass (p = 0.046), and 10% reduction in total blood volume (p = 0.02), albeit with no changes in the plasma volume.We conclude that direct measurement of blood volumes is useful for proper management of these patients, and provides results that are considerably different from those obtained by empirical estimations.


1982 ◽  
Vol 52 (5) ◽  
pp. 1186-1191 ◽  
Author(s):  
I. L. Kanstrup ◽  
B. Ekblom

The relative importance of blood volume (BV) for the maximum aerobic power (VO2 max) was evaluated in healthy subjects by sequential measurements without intervention under two conditions: 1) after hemodilution with a plasma expander, thus increasing BV but keeping red cell mass constant and lowering hemoglobin concentration [Hb], and 2) after whole blood withdrawal, which restored BV to control conditions but reduced red cell mass and [Hb] to equal conditions under 1. After BV expansion (avg 700 ml), we found an unchanged VO2 max compared with control data despite lowered [Hb]. Cardiac output (Q) was increased after BV expansion at rest and during all exercise levels (maximum 27.4 and 29.5 l . min-1, respectively). Peak stroke volume was increased from 144 to 173 ml. Arterial blood pressures were either unchanged or lowered. In contrast, after blood letting to a similar [Hb], we found a significantly reduced VO2 max. These findings indicate a significant influence of the size of the blood volume on cardiac performance. The increased Qmax is discussed in relation to preload, inotropic state, heart rate, and afterload. Plasma volume expansion causes increased preload which may explain this primary effect on the central circulation (Frank-Starling effect).


Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1059-1067 ◽  
Author(s):  
M Tavassoli

Abstract A consistent deficit in the red cell mass has been observed during both the American and Soviet orbital space flights and is sometimes referred to as “astronaut anemia.” This may be associated with a reduction in plasma volume so that the hematocrit and the hemoglobin concentration remain unchanged. During the Gemini program, the hypobaric hyperoxic atmosphere of the spacecraft led to oxidative injury to the red cells, causing hemolysis. Thus, the atmosphere proved to be, in part, responsible for the deficit. However, a similar deficit of a lesser magnitude was again observed in subsequent flights with normal ambient PO2 as well as in the Soviet flights in which an atmosphere essentially of see level air is used. The cause of this deficit seems to be suppression of erythropoiesis, as indicated by reticulocytopenia and erythroid hypoplasia of the marrow. No suppression of erythropoiesis has been observed in ground-based experiments carried out under almost identical conditions. Thus, the suppression of erythropoiesis is thought to be related to weightlessness. The reason for the suppression is not known but may be related to total inhibition of bone formation.


Blood ◽  
1970 ◽  
Vol 35 (3) ◽  
pp. 394-408 ◽  
Author(s):  
MALCOM R. MACKENZIE ◽  
ELLEN BROWN ◽  
H. H. FUDENBERG ◽  
LUCY S. GOODENDAY

Abstract In 17 patients with Waldenström’s Macroglobulinemia, total chromium space, red cell mass, plasma volume and relative serum viscosities were determined; aldosterone excretion was determined in 12. Ten of the 15 patients who manifested elevated serum viscosity at some time during the course of study presented signs and symptoms of hyperviscosity syndrome. All patients had increased total blood volume. Fifteen had moderate decreases in red cell mass but all had elevations of plasma volume far in excess of that required to compensate for the lowered cell mass. The degree of the increase in plasma volume correlated (r = 0.74) with the degree of abnormality in relative serum viscosity. Aldosterone excretion in such patients was normal to low. It is concluded that the plasma volume increase is correlated with serum viscosity and is mediated by sodium retention mechanisms not involving modification of aldosterone secretion.


Blood ◽  
1980 ◽  
Vol 56 (1) ◽  
pp. 125-128 ◽  
Author(s):  
N Mohandas ◽  
MR Clark ◽  
S Kissinger ◽  
C Bayer ◽  
SB Shohet

Abstract Because of discrepancies between electronically and manually measured values of mean cell hemoglobin concentration (MCHC) encountered in studies of pathologic red cells, we studied the effect of cell water content on MCHC measurements by both methods. A series of red cell samples with varying water contents (54%-164% normal) were prepared from normal cells using the antibiotic nystatin. MCHC was then measured, using the microhematocrit centrifuge and three different electronic cell counters in common laboratory use. For MCHC values above 36 g/dl as measured by the spun hematocrit method, all three electronic counters under estimmated the MCHC, with increasing error as the true MCHC increased. For MCHC values below 30 g/dl, the values from two conductivity based instruments agreed with those from the spun hematocrit method, whereas one instrument based on light scattering overestimated the MCHC. These results indicate that inaccuracies in the measured mean cell volume (MCV) of dehydrated or otherwise undeformable cells may lead to spurious values for MCHC when electronic cell counters are used.


1979 ◽  
Vol 237 (1) ◽  
pp. H71-H75 ◽  
Author(s):  
P. A. Mueggler ◽  
J. S. Peterson ◽  
R. D. Koler ◽  
J. Metcalfe ◽  
J. A. Black

Hematologic parameters influencing tissue oxygen delivery in dogs during the first 4 mo of life have been investigated. The rapid growth and increase in body temperature during this period imply an increased metabolic rate and increased tissue oxygen demand. Hemoglobin concentration and hematocrit decrease during the 1st mo following birth. The total red cell mass does not decrease during this period. The observed hemodilution can be attributed to an increasing plasma volume in the growing animal. The blood oxygen affinity decreases during this same period, resulting in a more effective tissue oxygen delivery. Erythropoiesis, as estimated from the percent circulating reticulocytes, decreases following birth and does not increase until 1 mo of postnatal life. The increase of erythropoietic activity during the 2nd mo of postnatal life coincides with an increase in red cell mass, hematocrit, and hemoglobin concentration.


2003 ◽  
Vol 13 (3) ◽  
pp. 251-265 ◽  
Author(s):  
Gordon Sleivert ◽  
Val Burke ◽  
Craig Palmer ◽  
Alan Walmsley ◽  
David Gerrard ◽  
...  

To determine the effects of deer antler velvet on maximal aerobic performance and the trainability of muscular strength and endurance, 38 active males were randomly assigned in a double-blind fashion to either deer antler velvet extract (n = 12), powder (n = 13), or placebo groups (n = 13). Subjects were tested prior to beginning supplementation and a 10-week strength program, and immediately post-training. All subjects were measured for circulating levels of testosterone, insulin-like growth factor, erythropoietin, red cell mass, plasma volume, and total blood volume. Additionally, muscular strength, endurance, and VO2max were determined. All groups improved 6 RM strength equivalently (41 ± 26%, p < .001), but there was a greater increase in isokinetic knee extensor strength (30 ± 21% vs. 13 ± 15%, p = .04) and endurance (21 ± 19% vs. 7 ± 12%, p = .02) in the powder compared to placebo group. There were no endocrine, red cell mass or VO2max changes in any group. These findings do not support an erythropoetic or aerobic ergogenic effect of deer antler velvet. Further, the inconsistent findings regarding the effects of deer antler velvet powder supplementation on the development of strength suggests that further work is required to test the robustness of the observation that this supplement enhances the strength training response and to ensure this observation is not a type I error.


1959 ◽  
Vol 197 (2) ◽  
pp. 403-405 ◽  
Author(s):  
Arthur E. Barnes ◽  
Wallace N. Jensen

A method for the determination of red cell mass, which employs the use of radioisotopically-labeled erythrocytes, in the embryonated hen egg is described and results of total blood volume, plasma volume, red cell mass and red cell concentration determinations during the period from 9 to 18 days of incubation presented. Considerations of the values obtained in terms of absolute quantities and relative to embryonic mass are discussed. It is suggested that expansion of the red cell mass and somatic growth are portions of a common process and may be subject to a complex of similar regulatory factors in the normal chick embryo.


Blood ◽  
1980 ◽  
Vol 56 (1) ◽  
pp. 125-128
Author(s):  
N Mohandas ◽  
MR Clark ◽  
S Kissinger ◽  
C Bayer ◽  
SB Shohet

Because of discrepancies between electronically and manually measured values of mean cell hemoglobin concentration (MCHC) encountered in studies of pathologic red cells, we studied the effect of cell water content on MCHC measurements by both methods. A series of red cell samples with varying water contents (54%-164% normal) were prepared from normal cells using the antibiotic nystatin. MCHC was then measured, using the microhematocrit centrifuge and three different electronic cell counters in common laboratory use. For MCHC values above 36 g/dl as measured by the spun hematocrit method, all three electronic counters under estimmated the MCHC, with increasing error as the true MCHC increased. For MCHC values below 30 g/dl, the values from two conductivity based instruments agreed with those from the spun hematocrit method, whereas one instrument based on light scattering overestimated the MCHC. These results indicate that inaccuracies in the measured mean cell volume (MCV) of dehydrated or otherwise undeformable cells may lead to spurious values for MCHC when electronic cell counters are used.


Blood ◽  
1982 ◽  
Vol 60 (5) ◽  
pp. 1059-1067 ◽  
Author(s):  
M Tavassoli

A consistent deficit in the red cell mass has been observed during both the American and Soviet orbital space flights and is sometimes referred to as “astronaut anemia.” This may be associated with a reduction in plasma volume so that the hematocrit and the hemoglobin concentration remain unchanged. During the Gemini program, the hypobaric hyperoxic atmosphere of the spacecraft led to oxidative injury to the red cells, causing hemolysis. Thus, the atmosphere proved to be, in part, responsible for the deficit. However, a similar deficit of a lesser magnitude was again observed in subsequent flights with normal ambient PO2 as well as in the Soviet flights in which an atmosphere essentially of see level air is used. The cause of this deficit seems to be suppression of erythropoiesis, as indicated by reticulocytopenia and erythroid hypoplasia of the marrow. No suppression of erythropoiesis has been observed in ground-based experiments carried out under almost identical conditions. Thus, the suppression of erythropoiesis is thought to be related to weightlessness. The reason for the suppression is not known but may be related to total inhibition of bone formation.


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