Normobaric hypoxia and sports: the debate continues

Abstract

We have read with interest the recent letter of SanchisGomar et al. (2010), and we basically agree with the authors who concluded that normobaric hypoxia can significantly modify several hematological parameters tested by anti-doping authorities so that anti-doping organizations should take into account the possibility of including normobaric hypoxia among the doping practices at least as a masking method in sports. Nevertheless, we raise several doubts about the fact that two out of three criteria presented by the World Anti-Doping Agency (WADA) for substances and methods to be considered for placement on the prohibited list (i.e., normobaric hypoxia does not exert significant ergogenic effects, and real or simulated altitude is quite safe and unlikely to injure an athlete) were considered by the authors not applicable to normobaric hypoxia.As regards the biological mechanisms supporting the potential ergogenic effect of normobaric hypoxia, these have been recently reviewed by Lemaître et al. (2010) and include (a) optimization of the stimuli needed to improve oxygen delivery while avoiding the detraining effects associated with chronic hypoxia, (b) the splenic contraction effect which increases both hematocrit and hemoglobin between 2 and 5% independently of hemoconcentration and reduces arterial oxygen desaturation, (c) the reduction of blood acidosis (which is enormously advantageous for exercise performance), oxidative stress, and basal metabolic rate, and (d) and the increase in lung volume. It was also recently observed that although 8 weeks of respiratory muscle training did not increase maximum oxygen uptake ð _

Effects of high‐intensity resistance circuit‐based training in hypoxia on body composition and strength performance

“…However, it is still unknown whether HRC or HRC under hypoxic conditions provides a sufficient stimulus to enhance bone mass. Lippi, Franchini, and Banfi (2011) has speculated that normobaric hypoxia is associated with unfavourable biochemical changes, such as decreased anti-oxidative capacity and increased lipid peroxidation. However, Wiesner et al (2010) have reported that not only the exercise but also hypoxia regulates pathways that are crucial to glucose and lipid metabolism.…”

“…Lippi, Franchini, and Banfi (2011) has speculated that normobaric hypoxia is associated with unfavourable biochemical changes, such as decreased anti‐oxidative capacity and increased lipid peroxidation. However, Wiesner et al.…”

Monitoring of biological markers indicative of doping: the athlete biological passport

“…Regarding the blood collection, beside the technical aspects66 67 of the blood draw (which must be performed after allowing a timeout period in a sitting position),1 the timing of the sample collection, the exercise68–70 and the exposure of the athlete to altitude (real or simulated)28 71 are regarded as very important for the stability of haematological markers. Then, the main points to be confirmed are the following:

No training or competition before the last 2 h of the blood test.

Did the athlete train, compete or reside at an altitude greater than 1000 m within the previous 2 weeks?

Did the athlete use any form of altitude simulation (hypoxic tent, mask, etc) during the previous 2 weeks?

Did the athlete receive or donate for any reason blood transfusion the previous 3 months?

…”

Laboratory medicine and sports: between Scylla and Charybdis

“…A sudden reassurance of autologous blood transfusions (i.e., correspondence between donor and receiver) occurred in the 2000s as a consequence of the development of reliable tests for detecting rHuEpo and related substances. The current history of blood doping is hence based on both autologous blood transfusions and novel blood boosting substances, such as continuous erythropoietin receptor activator (CERA) (42) or simulated altitude environments (43) , whereas erythrocyte-mimicking synthetic biomaterial particles (44) and gene doping (45) may represent additional threats for the future (46) .…”