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

Shoemaker, J. Kevin; Green, H. J.; Coates, James E.; Ali, M. Ayub; Grant, Sue

doi:10.1152/ajpheart.1996.270.1.h121

Cited by 16 publications

(30 citation statements)

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“…The fact that trained athletes have an elevated TBV and relatively normal Hct values suggests that at least in the males, the PV adaptation persists and RCV is increased. However, several studies, including our own (Shoemaker et al 1996) have not been able to document increases in RCV with vigorous training conducted for up to 11 weeks. If RCV can be elevated to the level suggested in trained athletes, it would appear that a much more vigorous and sustained exposure to exercise is needed.…”

Section: Discussionmentioning

confidence: 73%

“…The eect of training on RCV is not as clear. Although earlier studies have reported increases in RCV, recent studies using more accepted measurement procedures, with independent assessments of PV and RCV, have been unable to document changes, at least in response to training periods that have extended for up to 11 weeks and where 2 h of cycle exercise conducted ®ve to six times per week represented the training stimulus (Green et al 1991;Shoemaker et al 1996). Based on the inability of cycle training to increase RCV, two contradictory interpretations appear apparent, namely that the higher vascular volumes that are characteristic of the trained athlete are indeed an inherent characteristic of the trained athlete, or that the training stimulus was inappropriate for inducing the adaptations in RCV.…”

Section: Introductionmentioning

confidence: 99%

“…Conceivably, the nature of the activity (cycling versus running) could account for the failure of recent training studies to elicit adaptations in RCV (Green et al 1991Shoemaker et al 1996.…”

Section: Introductionmentioning

confidence: 99%

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Vascular volumes and hematology in male and female runners and cyclists

Green

Grant

et al. 1999

European Journal of Applied Physiology

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To examine the hypothesis that foot-strike hemolysis alters vascular volumes and selected hematological properties is trained athletes, we have measured total blood volume (TBV), red cell volume (RCV) and plasma volume (PV) in cyclists (n = 21) and runners (n = 17) and compared them to those of untrained controls (n = 20). TBV (ml x kg(-1)) was calculated as the sum of RCV (ml x kg(-1)) and PV (ml x kg(-1)) obtained using 51Cr and 125I-labelled albumin, respectively. Hematological assessment was carried out using a Coulter counter. Peak aerobic power (VO2peak) was measured during progressive exercise to fatigue using both cycle and treadmill ergometry. RCV was 15% higher (P < 0.05) in male cyclists [35.4 (1.0), mean (SE); n = 12] and runners [35.3 (0.98); n = 9] compared to the controls [30.7 (0.92); n = 12]. Similar differences existed between the female cyclists [28.2 (2.1); n = 9] and runners [28.4 (1.0); n = 8] compared to the untrained controls [24.9 (1.4); n = 8]. For the male athletes, PV was between 19% (cyclists) and 28% (runners) higher (P < 0.05) in the trained athletes compared to the untrained controls. The differences in PV between the female groups were not significant. Although the males had a higher (P < 0.05) TBV, RCV and PV than the females, no differences between cyclists and runners were found for either gender. Mean cell volume was not different between the athletic groups. VO2peak (ml x kg(-1) x min(-1)) was higher (P < 0.05) in both male [68.4 (1.5)] and female [54.8 (2.1)] runners when compared to the untrained males [47.1 (1.0)] and females [40.5 (2.1)]. Although differences existed between the genders in VO2peak for both cyclists and runners, no differences were found between the athletic groups within a gender. Since the vascular volumes were not different between cyclists and runners for either the males or females, foot-strike hemolysis would not appear to have an effect on that parameter. The significant correlations (P < 0.05) found between VO2peak and RCV (r = 0.64 and 0.64) and TBV (r = 0.82 and 0.63) for the males and females, respectively, suggests a role for the vascular system in realizing a high aerobic power.

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Section: Discussionmentioning

confidence: 73%

Section: Introductionmentioning

confidence: 99%

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Vascular volumes and hematology in male and female runners and cyclists

Green

Grant

et al. 1999

European Journal of Applied Physiology

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“…The rationale for assessing tHb in elite athletes is that Xuctuations in tHb above a certain magnitude (yet to be determined) could be indicative of doping. Although tHb can increase with training in combination with altitude exposure (Brugniaux et al 2006), it seems that tHb is stable (Eastwood et al 2008) and is not inXuenced much by brief periods of training (Green et al 1991;Shoemaker et al 1996). Data from longitudinal studies are scarce, but in active healthy subjects the assessment of tHb over 100 days showed variation of approximately 2% (Eastwood et al 2008).…”

Section: Introductionmentioning

confidence: 99%

Assessment of total haemoglobin mass: can it detect erythropoietin-induced blood manipulations?

Lundby

Robach²

2009

Eur J Appl Physiol

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The purpose of the study was to reveal erythropoietin (epo) doping. It was recently suggested that the assessment of total haemoglobin mass (tHb) by means of the carbon monoxide re-breathing technique should be implemented in anti-doping work. Since epo may increase the haemoglobin concentration [Hb] simply by reducing plasma volume we injected eight human subjects with epo for 15 weeks and directly tested the feasibility hereof. Epo treatment increased [Hb] in all subjects at all time points (range 3.8-18.8%). In approximately half the subjects this was mainly the consequence of an increased tHb, but in the remaining subjects the change was the result of a decrease in the plasma volume. After the initial epo "boosting" period the assessment of tHb could not detect epo injections in 50% of the subjects in the remaining "maintenance" period. In our opinion the variability observed over time when assessing tHb is not justifiable in an anti-doping setting.

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“…3). In contrast, a compelling weight of evidence indicates that exercise training does not increase RBC mass 38 , and further that highly trained humans might actually evidence a mild reduction in haematocrit 39 . The single report that a transient increase in [EPO] occurred 31 h following marathon running may have been the result of that particular event causing dehydration and an extended period of exercise-induced decreases in renal blood flow 17 .…”

Section: Effects Of Exercise On Plasma [Epo]mentioning

confidence: 99%

Effects of high altitude and exercise on plasma erythropoietin in equids

McKeever

Wickler

Smith

et al. 2010

Comp. Exerc. Physiol.

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To help resolve the mechanistic bases for haematological adaptations (, 28% increase in red blood cell volume) of equids to high altitude (3800 m, barometric pressure P b , 487 mm Hg) and exercise, plasma erythropoietin concentration ([EPO]) was measured at rest and following exercise in six, moderately fit equids (four Arabians, one Quarter Horse and one Shetland Pony; four females and two males; age 9.0^4.5 years (mean^SD)).[EPO] was measured on 2 days at 225 m (i.e. , sea level; P b , 743 mm Hg), over the course of a 10-day altitude exposure, and then again for 2 days after return to sea level. A standard track exercise test (submaximal, speed set-to-heart rate of 110 (trot), 150 (canter), 180 (gallop) bpm) was performed 2 days pre-high-altitude exposure and on three separate days at high altitude. In addition, a maximal incremental exercise test was performed on a high-speed motor-driven treadmill at sea level and 2 days following return to sea level from high altitude. Resting [EPO] increased from 28^29 at sea level to 144^46 mU ml 21 (P , 0.05) on the first day at high altitude. By day 2 at high altitude, [EPO] had returned to baseline (31^24 mU ml 21 , P . 0.05 vs. pre-high altitude) and did not change over the remaining 8 days at high altitude nor over the 2 days after return to sea level. [EPO] was not significantly altered by acute exercise at sea level or at 3800 m. These results indicate that [EPO] increases rapidly (though transiently) in response to hypobaric hypoxia but not to acute exercise, and that exercise does not appear to potentiate the altitude response. Thus, if any [EPO]-derived haematological adaptations to high altitude are present, these appear to result from a transient , 4-fold elevation of [EPO] rather than any sustained increase in this signalling mechanism, at least in the equid.

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

Cited by 16 publications

References 0 publications

Vascular volumes and hematology in male and female runners and cyclists

Vascular volumes and hematology in male and female runners and cyclists

Assessment of total haemoglobin mass: can it detect erythropoietin-induced blood manipulations?

Effects of high altitude and exercise on plasma erythropoietin in equids

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