C Lundby

..We hypothesised that a decrease in the BCAA/AAA ratio occurs along with a net cerebral influx of the neurotoxic AAA phenylalanine in a human experimental model of systemic inflammation...

..9 and 53.9% during the study period, this mechanism seems as important for increasing arterial oxygen content as the well-known erythropoietic effect of Epo...

..This would suggest that the major determinant V(o2max)for not to increase with acclimatization is the observed reduction in maximal leg blood flow and O(2) conductance...

..Peak cardiac output at altitude is not limited by excessive mean arterial pressure. Exercising leg .VO(2peak) is not limited by restricted vasodilatation in the altitude-acclimatized human...

..However, in contrast to our hypothesis, prolonged Epo administration had no apparent effect on capillarization or muscle fiber hypertrophy...

..The augmented hematocrit did not compromise peak cardiac output. In summary, in healthy humans, rHuEpo increases maximal oxygen consumption due to augmented systemic and muscular peak oxygen delivery...

..Recently the test has met serious critiques, and the aims of the present study were to investigate the detection power of the test as well as the variability in the test power comparing the results of two WADA-accredited laboratories...

..On the other hand, combining hypoxia with exercise appears to improve some aspects of muscle O(2) transport and/or metabolism...

..8% as compared to pre rHuEpo administration. In conclusion, in healthy non-athlete subjects rHuEpo administration prolongs submaximal exercise performance by about 54% independently of the approximately 12% increase in VO2max...

..High-altitude natives from the Andes actually exhibit a higher anaerobic energy production than lowlanders after 8 weeks of acclimatization reflected by an increased muscle lactate accumulation and enhanced adenine nucleotide breakdown...

..In conclusion, changes in muscle membrane transport proteins and selected muscle enzymes do not contribute to the Epo-induced improvement in performance...

..In conclusion, results from several, independent investigations indicate that exercise economy remains unchanged after acclimatization to high altitude...

..This study clearly demonstrates a progressive decrease in peak HR with increasing altitude, despite evidence of similar exercise effort and unchanged sympathetic excitation...

..0, before and after NESP treatment, respectively. NESP-injections in human subjects causes Hb and accordingly CaO2 to increase both in normoxia and hypoxia. Despite increases in CaO2 at maximal exercise in hypoxia VO2max is not increased...

..Together, these changes suggest a hypoxia-induced increase in the capacity for lactate, HCO3- and H+ fluxes from muscle to blood and from blood to erythrocytes...

..0+/-0.2 and 4.2+/-0.2 L min(-1). It is concluded that intermittent hypoxic exposure to 4100 m altitude for 2 h daily and a total of 14 days does not affect exercise capacity...

..4 mmHg). In conclusion, lowlanders substantially improve pulmonary gas exchange with acclimatization, but even acclimatization for 8 wk is insufficient to achieve levels reached by high-altitude natives...

..The peak heart rates at 8,750 m are in agreement with other field studies, but considerably higher than values reported from hypobaric chamber studies...

..05). In conclusion, human muscle VEGF mRNA expression and capillary density are not significantly increased by 8 weeks of exposure to high altitude and are not increased in Aymara high-altitude natives compared with sea level residents...

..2 +/- 0.02 g min(-1) in ACrel and 0.3 +/- 0.02 g min(-1) in CHrel. In conclusion, substrate utilization is unaffected by AH and CH, when the work rate is matched to the same relative intensity as at SL...

..9 +/- 0.8% in normoxia and -10.0 +/- 0.4% in hypoxia). It is concluded that leg net K(+) release is unrelated to anaerobic energy production and that acclimatization reduces leg net K(+) release during exercise...

..The hypothesis that brief intermittent exercise-induced increases in human skeletal muscle metabolic mRNA is dependent on relative workload was investigated...

..In our opinion the variability observed over time when assessing tHb is not justifiable in an anti-doping setting...

..We conclude that the plasma IL-6 concentration during exercise in hypoxia is intensity dependent, and that factors other than catecholamine levels are more important for its regulation...

..In addition, the present study shows that multiple muscle biopsies obtained from the same muscle do not influence the mRNA response induced by an acute exercise bout for any of the genes examined...

..Muscle enzyme activity was unaffected with altitude exposure in both groups, whereas muscle buffer capacity was increased...

..However, increased incorporation of membrane proteins during erythrocyte formation may also be involved. We suggest that NESP improves the quality of erythrocyte membrane transport through these mechanisms...

..Although the number of subjects is limited, these results imply that the adaptation pattern after long-term, prolonged, low-intensity, whole body exercise may vary dramatically among muscles...

..To investigate if exercise intensity and Ca(2+) signalling regulate Na(+),K(+) pump mRNA expression in skeletal muscle...

..However, 42% of our rHuEpo-injected subjects were not detected. It should be emphasised that the test frequency in real world anti-doping is far less than the present study, and hence the detection rate will be lower...

..To test the hypothesis that free fatty acid (FFA) and muscle glycogen modify exercise-induced regulation of PDH (pyruvate dehydrogenase) in human skeletal muscle through regulation of PDK4 expression...

..Most of the animal experimental models should be interpreted with caution because the assays for assessment of lipid peroxidation products have suboptimal validity...

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..We propose that HIFs expression is upregulated with exercise and that it may be an important transcription factor that regulates adaptive gene responses to exercise...

..The main objectives were to establish the period of detection of darbepoetin alfa by isoelectric focusing (IEF) and examine the applicability of blood algorithms and individual variations in blood variables in an antidoping context...

..In contrast to our hypothesis, we find that EPO augments the acute inflammatory effect...

..In conclusion, CGRP release during hypoxic exercise does not respond to domperidone-induced changes in circulating levels of noradrenaline, rather the release may be directly related to the production of lactate...

..Thus, in HA, the elevated iron requirement associated with enhanced erythropoiesis presumably elicits iron mobilization and myoglobin down-modulation, suggesting an altered muscle oxygen homeostasis...

..V(O(2)(max) during exercise in acute hypoxia. Likewise, reducing [Hb] in altitude-acclimatized humans to pre-acclimatization values has no effect on (.)V(O(2)(max) during exercise in hypoxia...

..In conclusion, activation of additional muscle mass does not result in a higher exercise-induced increase in Na(+)-K(+)-ATPase subunit-specific mRNA...

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