Power Balance Bracelets a Bust in IIG Test
November 11, 2010Power Balance Bracelets a Bust
On October 21st, 2010, members of the Independent Investigations Group www.iigwest.org , 15 volunteers, and former Olympic gymnast Dominique Dawes conducted a test of a product called Power Balance bracelets ($29.95 online) at the Center for Inquiry-Los Angeles. Dominique was there with Yahoo News which did a story and shot some video of our test.
Power Balance claims that the holograms on their bracelets work with the body's alleged (my word) energy field and improves strength, flexibility and balance by "optimizing the body's natural energy flow." I won't speculate about how this device might work as I am in the Ray Hyman school that says let's establish that it actually does work before trying to figure out how it works.
To support their claims, the company relies heavily on testimonials from blue-chip pro athletes like Lamar Odom of the L.A. Lakers and Derrick Rose of the Chicago Bulls. Odom and others are paid to endorse the product, and do wear them during games.
Power Balance, LLC, also uses highly subjective applied kinesiology tests to demonstrate the bracelets working. (One person analyzes another person's resistance and balance by applying pressure in various ways.) Watch this video to see how the company tests the bracelets.
This applied kinesiology method of testing the bracelet's effectiveness is problematic and full of flaws. There is no way to know from videos like this how much pressure the tester is exerting, whether the technique used to apply the pressure is identical each time, or whether the resistance from the person being tested is the same each time. And most people's flexibility seems to improve from their first stretch to their second stretch regardless of whether they are wearing the bracelet. (I invite you to try this for yourself using no bracelet.)
Also, the people being tested may unconsciously change their own resistance when they know the bracelet is on and think it should be helping. Indeed, the psychological influence of believing the bracelet will help may be the only real effect Power Balance can claim. Any athlete knows that confidence is an asset.
To remove this suggestive influence of the bracelets, we decided to test 15 volunteers and Dominique Dawes on a brief obstacle course that included a 16' balance beam, a figure-8-course run with two 30 lb dumbbells, and a stretch test. We taped up the bracelets so that none of the volunteers ever knew whether they were wearing a real Power Balance bracelet or one that had had the holograms removed. The power of suggestion was therefore eliminated.
In random order, each of the 16 volunteers went through the course 4 times - once with the real bracelet on and 3 times with the bracelets that had no holograms. (By the way, the test was double blind - none of the testers or volunteers had any idea when or if they were wearing a real bracelet until well after the test was over.)
By the end of the test, each of the 4 bracelets we used (3 empty ones and one genuine) had been carried through the course a total of 16 times. (We spread the bracelets equally among the volunteers through the 4 rounds of trials to insure that no bracelet had a numerical advantage at any given time.)
So what happened?
We're working on a full report that will be released in the near future, but I can say this:
If the one genuine Power Balance bracelet had an intrinsic value that really does confer better balance, flexibility and strength on the user, we should have seen cumulatively better scores when people wore it. When compared to the 3 "dummy" bracelets, the real one should have stood out with lower times and better flexibility.
That did not happen.
The scores between the 4 bracelets were very close together - exactly what you would expect to see if there was no significant effect from wearing the Power Balance bracelets. (In the obstacle course times, the genuine bracelet actually scored slightly worse , though not statistically significantly worse.)
Our initial conclusion is that Power Balance bracelets have no discernable effect when the wearer doesn't know if he has one on or not. In other words, the bracelet itself doesn't seem to be doing anything.
As a sort of rabbit's foot to be worn to boost one's confidence, the bracelet might have some value, but as a boon to one's athletic prowess, Power Balance bracelets are a bust.
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