title: Haemoglobin mass and running time trial performance after recombinant human erythropoietin administration in trained men.
abstract: Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hb(mass)) and maximal oxygen uptake (v O(2 max)).
  
  
  OBJECTIVE
  This study defined the time course of changes in Hb(mass), v O(2 max) as well as running time trial performance following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual improvements in running performance in the field.
  
  
  METHODS
  19 trained men received rHuEpo injections of 50 IU•kg(-1) body mass every two days for 4 weeks. Hb(mass) was determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. v O(2 max) and 3,000 m time trial performance were measured pre, post administration and at the end of the study.
  
  
  RESULTS
  Relative to baseline, running performance significantly improved by ∼6% after administration (10:30±1:07 min:sec vs. 11:08±1:15 min:sec, p<0.001) and remained significantly enhanced by ∼3% 4 weeks after administration (10:46±1:13 min:sec, p<0.001), while v O(2 max) was also significantly increased post administration (60.7±5.8 mL•min(-1)•kg(-1) vs. 56.0±6.2 mL•min(-1)•kg(-1), p<0.001) and remained significantly increased 4 weeks after rHuEpo (58.0±5.6 mL•min(-1)•kg(-1), p = 0.021). Hb(mass) was significantly increased at the end of administration compared to baseline (15.2±1.5 g•kg(-1) vs. 12.7±1.2 g•kg(-1), p<0.001). The rate of decrease in Hb(mass) toward baseline values post rHuEpo was similar to that of the increase during administration (-0.53 g•kg(-1)•wk(-1), 95% confidence interval (CI) (-0.68, -0.38) vs. 0.54 g•kg(-1•)wk(-1), CI (0.46, 0.63)) but Hb(mass) was still significantly elevated 4 weeks after administration compared to baseline (13.7±1.1 g•kg(-1), p<0.001).
  
  
  CONCLUSIONS
  Running performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated v O(2 max) and Hb(mass).
authors: Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors: Jérôme
authors: J
authors: Durussel
authors: Evangelia
authors: E
authors: Daskalaki
authors: Martin
authors: M
authors: Anderson
authors: Tushar
authors: T
authors: Chatterji
authors: Diresibachew H
authors: DH
authors: Wondimu
authors: Neal
authors: N
authors: Padmanabhan
authors: Rajan K
authors: RK
authors: Patel
authors: John D
authors: JD
authors: McClure
authors: Yannis P
authors: YP
authors: Pitsiladis
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001810:Blood Volume / Q000187:drug effects; D002263:Carboxyhemoglobin / Q000378:metabolism; D004334:Drug Administration Schedule; D004921:Erythropoietin / Q000008:administration & dosage* / Q000235:genetics; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007279:Injections, Subcutaneous; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D010807:Physical Endurance / Q000187:drug effects* / Q000502:physiology; D011994:Recombinant Proteins / Q000008:administration & dosage; D012420:Running / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult
chemical_list: D006454:Hemoglobins; D011994:Recombinant Proteins; D004921:Erythropoietin; D002263:Carboxyhemoglobin