Silicone wrist bands and other “performance jewellery” have become commonplace among sports stars (see Paul Collingwood and Andrew Strauss, England cricketers, who are bedecked in several varieties). Power Balance, Harmony, Ionic, Q-Ray, Balance, Bio-Ray, IRenew and Rayma are some of the many brands that you might see online or in sports stores. I have been writing about negative ions and balance bands for a few years now, but most of that focused on the inherent lack of a plausible mechanism by which the things could work. Since I wrote those posts, there have been a number of clinical trials published, and I thought it would be worth trying to pull some of those together to provide an overview of the science. I have linked to all the studies so you can check them out yourself.
Summary: I found seven studies: four journal articles, one MSc thesis, one research poster, and one conference presentation which was an expansion of a journal article. The studies included a total of 193 participants and looked mainly at balance, strength and agility, all using the Power Balance band (in which holograms are the supposedly active part). None showed any improvement in performance with the band, but study quality varied. Interestingly, some studies suggest that the placebo effect might not even be present. However, another study showed that the placebo effect with this product is strongly dependent upon prior beliefs, and that performance may even suffer while wearing a band if the participant does not believe that the band will help. I was not able to find any tests of bands in which “ions” were purported to be the mode of action.
Study 1 – Verdan et al. (2012)
Type of study: Counterbalance, double-blind, placebo-controlled, within-subject design
Product tested: Power Balance Bands
Number of participants: 24 (M=10, F=14)
Measured outcome: Static balance, hamstring flexibility, and arm strength (see paper for details of how each was measured)
Details: Each participant was treated in three sessions: first with the PBB, second with a “placebo band”, and third with no band.
Result: No difference between band treatments.
Reference: Verdan, PJR, Marzilli, TS, Barna, GI, Roquemore, AN, Fenter, BA, Blujus, B, and Gosselin, KP. Effect of the Power Balance® band on static balance, hamstring flexibility, and arm strength in adults. J Strength Cond Res 26(8): 2113–2118, 2012
Study 2 – Reimnitz (2012) [note that this is a MSc thesis, rather than a peer-reviewed paper]
Type of study: Partially double-blind, placebo-controlled, within-subject design
Product tested: “Power Balance Bracelet”
Number of participants: 20 (M=20, F=0)
Measured outcome: Agility, flexibility (sit and reach), vertical jump, and chest press (see paper for methodological details)
Details: Participants performed tests for the four different measures on three different occasions: the first was the treatment with no band, and then the second and third were randomly allocated either the placebo or Power Balance band.
Result: No significant difference in agility, flexibility or vertical jump. There was a significant difference in chest press between the no band treatment and the two band (placebo and Power Balance) treatments. However, there was no difference between the placebo and Power Balance bands.
Reference: Reimnitz, RL (2012) The effect of the Power Balance bracelet on strength, agility, flexibility and vertical jump in collegiate male athletes. Masters Theses. Paper 975. East Illinois University.
Study 3 – Joseph et al. (2012) [note that this is a conference presentation, but it is based on a peer-reviewed study (see below)]
Type of study: Double-blind, placebo-controlled, within-subject design
Product tested: “Power Balance” band
Number of participants: 35 (male Australian Rules footballers=15; healthy adults: M=8, F=12)
Measured outcome: Various aspects of static balance
Details: All participants were tested on three occasions with three treatments: no band, placebo band and Power Balance band (randomly allocated to each session).
Result: No difference between or within groups.
Reference: Joseph, C., Furness, T., Buttifant, D., Naughton, G. (2012) Effect of performance jewelry on balance of elite Australian Rules footballers and healthy young adults, Conference presentation, International Conference on Biomechanics in Sport, Melbourne, 2012.
Associated paper: Furness, T., Joseph, C., Buttifant,, D., Naughton, G., Crowe, J. (2011) The affect of Power Balance® wrist bands on dynamic balance of elite Australian Rules Football players, Journal of Science and Medicine in Sport, Volume 14, Supplement 1, December 2011, Page e38
Study 4 – Brice et al. (2011)
Type of study: Partially double-blind, placebo-controlled, within-subject design
Product tested: “Power Balance Bracelet”
Number of participants: 42 (M=19, F=23)
Measured outcome: Balance and stability
Details: A “placebo” band was created by removing the holograms from the Power Balance band and replacing them with steel discs of the same size and weight. All participants were tested twice with each of three treatments (no band, placebo band, Power Balance band). On each visit they were randomly allocated the sequence “placebo-no band-Power Balance” or “Power Balance-no band-placebo”.
Result: No difference in balance between treatments – the authors highlight that there was not even a placebo effect from the presence of a band (as was seen in Reimnitz (2012)).
Reference: Brice, S., Jarosz, B., Ames, R. & Da Costa, C. (2011). The effect of close proximity holographic wristbands on human balance and limits of stability: A randomised, placebo-controlled trial. Journal of Bodywork & Movement Therapies, 15, 298-303.
Study 5 – Pothier et al. (2012) [I couldn’t access this one, so the details are sparse…]
Type of study: Single-blind, randomized, within-subject, triple placebo-controlled
Product tested: Power Balance Silicone Wristband
Number of participants: 20 (M=?, F=?)
Measured outcome: Balance
Details: Three different forms of placebo were created: no band, a different silicon band, and a “deactivated Power Balance Band” (with holograms removed).
Result: No difference between band treatments.
Reference: Pothier DD, Thiel G, Khoo SG, Dillon WA, Sulway S, Rutka JA. (2010) Efficacy of the Power Balance Silicone Wristband: a single-blind, randomized, triple placebo-controlled study., J Otolaryngol Head Neck Surg., 41(3):153-159.
Study 6 – Porcari et al (2011)
Type of study: Double-blind, randomised, placebo-controlled, within-subject
Product tested: “Power Balance Bracelet”
Number of participants: 42 (M=22, F=20)
Measured outcome: Trunk flexibility, balance, strength, and vertical jump
Details: Paper gives no details on how the placebo band was created, but this news article states that the placebo was a “$0.30 rubber bracelet”.
Result: No difference in any of the four measures between treatments.
Reference: Porcari,J., Hazuga, J., Foster, C., Doberstein, S., Becker, J., Kline, D., Mickschl, T., Dodge, C. (2011) Can the Power Balance bracelet improve balance, flexibility, strength, and power? Journal of Sports Science and Medicine 10, 230 – 231.
Study 7 – Wiley (2012) [a graduate student’s poster]
Type of study: Unblinded, placebo-controlled, within-subject
Product tested: Power Balance Band
Number of participants: 30 (M=15, F=15)
Measured outcome: Strength, agility, power, and rate of perceived exertion (RPE).
Details: This study was a little bit different. The participants were tested for each of the three measures of athletic ability (leg strength, lower body power, and agility) with RPE recorded after each. They were tested on two separate days with a rest day in between, and on each testing day participants were measured for all three performance tasks in both placebo and device treatments (in a random order). However, following the second day, the participants were given an exit survey to establish the extent to which they believed that the Power Balance Band would help.
Result: The study found that there was no overall difference between wearing a band or not wearing a band. However, believers in the band improved significantly while wearing the band, while non-believers declined in performance while wearing the band – on average there was no effect.
Reference: Wiley, M. (2012) The Placebo Effect of the Power Balance Band on Muscle Strength, Agility, Power and RPE, Cardiovascular Research Laboratory, University of Texas at Arlington.
Katatrepsis 