The makers of the Power Balance bracelet worn by footballer David Beckham have admitted there is no evidence that the wildly popular wristbands boost sporting prowess.
The admission came after Australia's consumer watchdog said the California-based company behind the wristbands and pendants had no business claiming that the colourful silicone bands improved balance, strength and flexibility.
After an agreement with the Australian Competition and Consumer Commission last month, Power Balance wrote: "We admit that there is no credible scientific evidence that supports our claims."
It also agreed to give refunds to customers who believe they were cheated.
Critics railed against the company on Twitter and those who had believed in the bracelet's power and the company unleashed a torrent of its own tweets, playing on the word "admit".
In one, it said: "Power Balance Admits products have been worn during the last world series, nba finals and super bowl champions!"
US basketball star Shaquille O'Neal swears by the bracelet, which he says gives him a competitive edge on the court. And fans insist the bands have helped their game. "Our trainers swear by it," Phoenix Suns basketball forward Jared Dudley wrote on his Twitter page.
The company began selling bracelets in 2007 embedded with holograms purportedly designed to interact with the body's natural energy flow.
Since then, the wristbands, which sell for just over £19, have become ubiquitous, donned by Los Angeles Lakers' Lamar Odom and former England captain Beckham. They have also been worn by celebrities including actors Robert De Niro and Gerard Butler.
Power Balance expects to have made more than £22.5 million in sales for 2010. Adam Selwyn, a spokesman for the company, based in Laguna Niguel, California, said Power Balance did not claim to have science on its side, but relied on testimonials from famous athletes and users to tout the products' effects.