Power Balance Bracelets a Bust in Tests
Members of the Independent Investigations Group and sixteen volunteers, including former Olympic gymnast Dominique Dawes, conducted a test of Power Balance bracelets. The results will not be surprising to skeptics.
Power Balance bracelets are silicone wristbands that are embedded with two Mylar holograms. On October 21, 2010, the Independent Investigations Group (IIG) conducted a double-blind test to determine whether Power Balance’s claims that the holograms on their bracelets (then selling online for $29.95) work with the body’s “energy field” to improve strength, flexibility, and balance by “optimizing the body’s natural energy flow.” The company’s website also included a tangle of information that attempted to draw connections between Eastern medicine, “body frequencies,” and “positive energy.” The following excerpt, once available on the Power Balance site, gives insight into the company’s rationale behind its product: “Most everything has a frequency inherent to it. Some frequencies react positively with your body and others negatively. When the hologram comes in contact with your body’s energy field, it allows your body to interact with the natural, beneficial frequency stored within the hologram. This results in improved energy flow throughout your body.” (See Harriet Hall’s excellent article about these claims, “Power Balance Technology: Pseudoscientific Silliness Suckers Card-Carrying Surfers,” in the May/June 2010 Skeptical Inquirer; also available online.) The company relies heavily on testimonials from blue-chip pro athletes like Shaquille O’Neal of the Boston Celtics, Lamar Odom of the Los Angeles Lakers, and Derrick Rose of the Chicago Bulls. Odom and others are paid to endorse the product and do wear the bracelets during games.
Power Balance once used highly subjective applied kinesiology tests to demonstrate that the bracelets work. In these types of “tests,” one person analyzes another’s resistance and balance by applying pressure in various ways. (The applied kinesiology videos are no longer on Power Balance’s website, www.powerbalance.com.)
The applied kinesiology method of testing the bracelet’s effectiveness is problematic and full of flaws for a number of reasons. There is no way to know from videos of these tests 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. 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 effect of believing the bracelet will help may be the only real effect Power Balance can claim. Every athlete knows that confidence is an asset.
To remove this suggestive influence of the bracelets, we decided to test sixteen volunteers, including former Olympic gymnast Dominique Dawes, on a brief obstacle course that included a 16’×4”×4” balance beam, a figure-eight–shaped course (which our volunteers ran while holding two thirty-pound dumbbells), and a stretch test. Dawes was there with Yahoo News, which shot some video of our test for a story. Dawes, by the way, arrived with a healthy skepticism that seemed to get even stronger when she learned of the test results.
In random order, each of the sixteen volunteers went through the course four times: once with the real bracelet on and three times with each of the bracelets that had no holograms. The test was double blind; we taped over the bracelets so that no one—volunteers and testers alike—knew whether each volunteer was wearing a real Power Balance bracelet or one that had had the holograms removed. The power of suggestion was therefore eliminated.
By the end of the test, each of the four bracelets (labeled A, B, C, D)—three sans hologram and one “genuine”—had been carried through the course a total of sixteen times. We distributed the bracelets equally among the volunteers through all four rounds of trials to ensure that no bracelet had a numerical or sequential advantage at any given time. (We considered that the experience of running the course in early trials might help the subjects improve their times in their subsequent attempts. To correct for improving scores due to familiarity with the course—sometimes called the “Order Effect”—four people wore bracelet A in the first round, four different people wore bracelet A in the second round, and so on, for each of the four rounds.)
So what happened?
If the one genuine Power Balance bracelet had an intrinsic value that really did confer better balance, flexibility, and strength upon its user, we should have seen cumulatively better scores from the people who wore that bracelet (C) when compared to the people wearing the three “dummy” bracelets (A, B, and D). The overall scores between the four bracelets were in fact very close together: half the participants who wore the real bracelet did slightly better, and half did slightly worse—exactly as would be expected by chance. Table 1 shows the results of the obstacle course. Bear in mind that a lower time indicates a better performance. When it came to flexibility, the results were much the same: the overall scores were very close. This time, the Power Balance bracelet (also C in Table 2) fared slightly better than the other bracelets but, again, not significantly so.
Our initial conclusion was that Power Balance bracelets have no discernable effect when the wearer doesn’t know whether or not he or she is wearing one with a hologram. In other words, the bracelet itself doesn’t seem to be doing anything. These results are consistent with work done by Richard Saunders for the Australian Skeptics (see “Power Balance Down and Out,” SI, News and Comment, September/October 2011) and by John Porcari at the University of Wisconsin at Lacrosse, both of whom conducted blinded tests of Power Balance’s efficacy and found no difference between Power Balance products and dummy stand-ins used to blind the user.
The IIG at CFI–Los Angeles has now added its findings to the growing pool of Power Balance’s negative test results. Although the bracelet might have some value as a sort of rabbit’s foot meant to boost one’s confidence, Power Balance bracelets are a bust as a boon to one’s athletic prowess.