“Super-oxygenated” water was sold in the 90’s by several manufacturers who claimed that it would improve athletic stamina and performance. However, studies have shown the product to have no measurable physiological effects on performance.
The current study looked at what happens when athletes don’t know about the research related to super-oxygenated water, and who believe they are getting a performance boost from the product. Can a placebo effect significantly improve athletic performance?
Participants were 32 volunteer runners, aged 18 to 55, who ran a minimum of 16 km per week. They were shown a video detailing the benefits of super oxygenated water (SOW) and how the product might enhance their performance. After a baseline V02max measurement, each participant ran three time trials of 5 km each. During the second run, half the participants drank a bottle of what they were told was SOW, which was in fact just tap water. During the third run, the groups switched and the half that didn’t the false SOW during the second run, drank it this time. Heart rate, perceived exertion and blood lactate levels were monitored in all participants.
Heart rate, blood lactate levels and perceived exertion were nearly identical between the two groups. Interestingly, however, there was a significant difference in lap time average between the groups. Those who thought they were drinking SOW ran an average of 83 seconds faster (3.3 seconds per lap). Eighty four percent of the participants ran faster when drinking the placebo. Even more interesting was the fact that slower runners reduced their lap time significantly more than faster runners did, when they thought they were drinking SOW. This means the placebo effect was more pronounced in the less fit subjects.
These results are remarkable because heart rate, perceived exertion and blood lactate levels were the same in both groups, despite the differences in performance. The placebo effect has previously been show to reduce pain and inflammation, and this study reinforced those results, demonstrating improved performance without any change in physiologic parameters.