Letter to the Editor - Does Oxygenated Water Support Aerobic Performance and Lactate Kinetics?

Dear Editor,

The results reported in the publication entitled “Does Oxygenated Water Support Aerobic Performance and Lactate Kinetics?” by Leibetseder et al. [[6]] in the issue of the Int J Sports Med 2006; 27: 232 - 235 are important, as unsubstantiated claims are often found for sport foods and sport supplements.

The double-blind crossover study design, the number of the subjects (20), the well-defined exercise test procedure, the adequacy of measurements and the large volume of O₂-water ingested (1.5 liters) daily are consistent with a well-controlled study. However, this study deserves a few questions and comments in relation to the administration of water and previous literature not mentioned.

The authors do not indicate how and when the 1.5 liters of water were drunk during the day. In the other study mentioned in their references [[7]] and in another study not mentioned [[3]], water was ingested just before the test or the exercise and the volumes taken were 300 - 355 ml and the oxygen content of the water 60 - 300 mg O₂ per liter, respectively. While the first study showed a transient and moderate systemic generation of radicals in sedentary healthy volunteers, the second study would be worth discussing as it concerns the effect of oxygenated water in athletic performance. Hampson et al. [[3]] showed with a double-blind protocol that drinking oxygenated water five minutes before a graded maximal exercise has no significant effect on maximal oxygen uptake, carbon dioxide production, respiratory quotient ratio, peak heart rate and minute ventilation at peak exercise when compared with the same water brand that had been deoxygenated by agitation in air. These results obtained with an acute and well-defined administration of a volume of water that can be swallowed in one gulp do not support the statement of enhanced sport performance frequently claimed. As wide variations of oxygen concentrations were shown depending on a plastic or glass bottle [[3]] and when the bottle is opened [[6]], it is important to know how the subjects were instructed to drink 1.5 liters of oxygenated water daily for two weeks being sure that there was no oxygen losses.

In addition to this practical question, the metabolic fate of oxygen through oxygenated water ingestion raises some comments. Both studies [[3], [6]] made the hypothesis of a transfer of oxygen to the arterial blood, and it is even mentioned that more O₂ is provided from a single breath than by a bottle of oxygenated water [[3]]. When O₂ is provided intragastrically, studies performed on animal models [[2], [4]] and in humans [[1], [5]] have shown enhanced oxygen delivery to the gut wall and a rapid absorption of O₂ with an increased O₂ concentration in the portal blood. In patients, O₂ saturation of portal blood increases from 55 ± 7.2 % to 80 ± 6.2 % [[1]]. In the anaesthetized dog, measurements of oxygen tensions in the portal blood increased 7 - 8 % and lasted for 10 - 15 minutes after infusion of oxygenated water [[4]]. This increased supply of O₂ from oxygenated water consumption directly to the liver explains why more studies were performed on liver enzyme activities and the generation of oxygen radicals. While contradictory results were published on alcohol-dehydrogenase with a 60 % increase elimination rate of ethanol in monkeys [[4]] and no effect in healthy subjects [[5]], getting oxygen through drinks instead of breath is certainly more a safety issue than an increased supply of oxygen to muscle for an improved sport performance.

It is thus important to draw the attention of the reader that it is not the small amount of oxygen delivered to the peripheral blood, which must be considered, but the unusual supply of oxygen through portal veins to organs such as the liver. While both studies conclude with the absence of ergogenic effect of oxygenated water, the risk/benefit of drinking these oxygenated waters in normal individuals and sportsmen still needs to be carefully evaluated.

References

• 1 Gelman S I. The effect of enteral oxygen administration on the hepatic circulation during halothane anaesthesia: clinical observations.  Br J Anaesth. 1975;  47 1261-1264
• 2 Gelman S I, Paz M, Levy E. Influence of enteral oxygen administration on the slow electrical activity of the intestine and stomach.  Arch Surg. 1976;  111 566-574
• 3 Hampson N B, Pollock N W, Piantadosi C A. Oxygenated water and athletic performance.  JAMA. 2003;  290 2408-2409
• 4 Hyvärinen J, Laakso M, Sippel H, Roinew R, Huopaniemi T, Leinonen L, Hytönen V. Alcohol detoxification accelerated by oxygenated drinking water.  Life Sci. 1978;  22 553-559
• 5 Laasko M, Huopaniemi T, Hyvärinen J. et al . Inefficacy of oxygenated drinking water in accelerating ethanol elimination in humans.  Life Sci. 1979;  25 1369-1372
• 6 Leibetseder V, Strauss-Blasche G, Marktl W, Ekmekcioglu C. Does oxygenated water support aerobic performance and lactate kinetics.  Int J Sports Med. 2006;  27 232-235
• 7 Schoenberg M H, Hierl T C, Zhao J. et al . The generation of oxygen radicals after drinking of oxygenated water.  Eur J Med Res. 2002;  7 109-116