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1.
Eur J Appl Physiol ; 113(5): 1199-211, 2013 May.
Article in English | MEDLINE | ID: mdl-23138148

ABSTRACT

Aim of the study was to determine the influence of classic altitude training on hemoglobin mass (Hb-mass) in elite swimmers under the following aspects: (1) normal oscillation of Hb-mass at sea level; (2) time course of adaptation and de-adaptation; (3) sex influences; (4) influences of illness and injury; (5) interaction of Hb-mass and competition performance. Hb-mass of 45 top swimmers (male 24; female 21) was repeatedly measured (~6 times) over the course of 2 years using the optimized CO-rebreathing method. Twenty-five athletes trained between one and three times for 3-4 weeks at altitude training camps (ATCs) at 2,320 m (3 ATCs) and 1,360 m (1 ATC). Performance was determined by analyzing 726 competitions according to the German point system. The variation of Hb-mass without hypoxic influence was 3.0 % (m) and 2.7 % (f). At altitude, Hb-mass increased by 7.2 ± 3.3 % (p < 0.001; 2,320 m) and by 3.8 ± 3.4 % (p < 0.05; 1,360 m). The response at 2,320 m was not sex-related, and no increase was found in ill and injured athletes (n = 8). Hb-mass was found increased on day 13 and was still elevated 24 days after return (4.0 ± 2.7 %, p < 0.05). Hb-mass had only a small positive effect on swimming performance; an increase in performance was only observed 25-35 days after return from altitude. In conclusion, the altitude (2,320 m) effect on Hb-mass is still present 3 weeks after return, it decisively depends on the health status, but is not influenced by sex. In healthy subjects it exceeds by far the oscillation occurring at sea level. After return from altitude performance increases after a delay of 3 weeks.


Subject(s)
Altitude , Hemoglobins/analysis , Swimming/physiology , Acclimatization , Adaptation, Physiological , Adolescent , Adult , Athletes , Athletic Performance , Case-Control Studies , Female , Humans , Male , Sex Factors
2.
Scand J Med Sci Sports ; 21(6): e365-71, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21535184

ABSTRACT

The sensitivity of the athlete blood passport to detect blood doping may be improved by the inclusion of total hemoglobin mass (Hb(mass)), but the comparability of Hb(mass) from different laboratories is unknown. To optimize detection sensitivity, the analytical variability associated with Hb(mass) measurement must be minimized. The aim of this study was to investigate the efficacy of using quality controls to minimize the variation in Hb(mass) between laboratories. Three simulated laboratories were set up in one location. Nine participants completed three carbon monoxide (CO) re-breathing tests in each laboratory. One participant completed two CO re-breathing tests in each laboratory. Simultaneously, quality controls containing Low (1-3%) and High (8-11%) concentrations of percent carboxyhemoglobin (%HbCO) were measured to compare hemoximeters in each laboratory. Linear mixed modeling was used to estimate the within-subject variation in Hb(mass), expressed as the coefficient of variation, and to estimate the effect of different laboratories. The analytic variation of Hb(mass) was 2.4% when tests were conducted in different laboratories, which reduced to 1.6% when the model accounted for between-laboratory differences. Adjustment of Hb(mass) values using quality controls achieved a comparable analytic variation of 1.7%. The majority of between-laboratory variation in Hb(mass) originated from the difference between hemoximeters, which could be eliminated using appropriate quality controls.


Subject(s)
Hemoglobins/analysis , Performance-Enhancing Substances/isolation & purification , Quality Control , Substance Abuse Detection/standards , Adult , Australian Capital Territory , Doping in Sports , Female , Humans , Laboratories/standards , Male , Substance Abuse Detection/methods , Young Adult
3.
Scand J Med Sci Sports ; 21(2): 235-43, 2011 Apr.
Article in English | MEDLINE | ID: mdl-19903320

ABSTRACT

Blood passport has been suggested as an indirect tool to detect various kinds of blood manipulations. Autologous blood transfusions are currently undetectable, and the objective of this study was to examine the sensitivities of different blood markers and blood passport approaches in order to determine the best approach to detect autologous blood transfusions. Twenty-nine subjects were transfused with either one (n=8) or three (n=21) bags of autologous blood. Hemoglobin concentration ([Hb]), percentage of reticulocytes (%ret) and hemoglobin mass (Hbmass) were measured 1 day before reinfusion and six times after reinfusion. The sensitivity and specificity of a novel marker, Hbmr (based on Hbmass and %ret), was evaluated together with [Hb], Hbmass and OFF-hr by different passport methods. Our novel Hbmr marker showed superior sensitivity in detecting the highest dosage of transfused blood, with OFF-hr showing equal or superior sensitivities at lower dosages. Hbmr and OFF-hr showed superior but equal sensitivities from 1 to 4 weeks after transfusion compared with [Hb] and Hbmass, with Hbmass being the only tenable prospect to detect acute transfusions. Because autologous blood transfusions can be an acute practice with blood withdrawal and reinfusion within a few days, Hbmass seems to be the only option for revealing this practice.


Subject(s)
Blood Transfusion, Autologous , Doping in Sports/prevention & control , Hemoglobins/analysis , Reticulocytes , Substance Abuse Detection/methods , Adult , Biomarkers/blood , Humans , Male , Sensitivity and Specificity , Young Adult
4.
Scand J Med Sci Sports ; 18 Suppl 1: 57-69, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18665953

ABSTRACT

It is controversially discussed whether soccer games should be played at moderate (2001-3000 m) and high altitudes (3001-5500 m) or should be restricted to near sea level and low altitude (501-2000 m) conditions. Athletes living at altitude are assumed to have a performance advantage compared with lowlanders. One advantage of altitude adaptation concerns the expansion of total hemoglobin mass (tHb-mass), which is strongly related to endurance performance at sea level. Cross-sectional studies show that elite athletes posses approximately 35% higher tHb-mass than the normal population, which is further elevated by 14% in athletes native to altitude of 2600 m. Although the impact of this huge tHb-mass expansion on performance is not yet investigated for altitude conditions, lowland athletes seek for possibilities to increase tHb-mass to similar levels. At sea level tHb-mass is only moderately influenced by training and depends more on genetic predisposition. Altitude training in contrast, using either the conventional altitude training or the live high-train low (>14 h/day in hypoxia) protocol for 3-4 weeks above 2500 m leads to mean increases in tHb-mass of 6.5%. This increase is, however, not sufficient to close the gap in tHb-mass to elite athletes native to altitude, which may be in advantage when tHb-mass has the same strong influence on aerobic performance at altitude as it has on sea level.


Subject(s)
Blood Volume , Physical Fitness , Altitude , Hemoglobins/analysis , Humans , Oxygen Consumption , Soccer
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