Power Balance bracelets: source of energy or just a gimmick?

They are talking about a body's energy fields and natural frequency with the same enthusiasm that you might once have only heard around the stalls of Glastonbury festival or during summer solstice at Stonehenge.

It is because of sport's latest fad, a rubber wristband with a small hologram attached that, according to the manufacturers, helps to optimise the natural flow of energy around the body, and so improve an athlete's strength, balance and flexibility.

Footballers David Beckham and Cristiano Ronaldo have been seen wearing the Power Balance bracelets, which have supposedly been designed to "resonate with and respond to the natural energy field of the body". Basketball player Shaquille O'Neal and racing driver Rubens Barrichello are so convinced by the wristbands that they endorse them. "I don't do a lot of testimonials, but this works," claimed O'Neal, while Barrichello said: "I will never take the Power Balance off my body."

This year's final of the pre-Wimbledon Queen's Club tournament was an all-Power Balance affair, as both Sam Querrey and Mardy Fish took to the court with the rubber accessory. In addition, several players at Wasps rugby club wear them on the training pitch, in the gym and on match-days. A spokeswoman for Power Balance said that sprinter Mark Lewis-Francis and England cricketer Kevin Pietersen had also worn the bands.

Inevitably, there are sceptics who wonder how a wristband could possibly make you run faster, jump higher or drive faster, and think that this is at best a placebo and, at worst, a lot of expensive nonsense, with each one costing £30.

A group called the Australian Sceptics, who "investigate pseudoscience and the paranormal from a responsible scientific viewpoint", do not believe that the bands on Beckham's, Ronaldo's and Barrichello's wrists do what they are said to do, and two leading sports psychologists contacted by The Daily Telegraph said they would not encourage their clients to use the bracelets.

Jeremy Snape, who has worked with the England cricket team, said he would rather that athletes have belief in themselves without "putting their trust in external products", and Roberto Forzoni, who has worked with the Football Association and the Lawn Tennis Association, described the bands as "gimmicks".

"As with many of these gimmicks, athletes look for a quick and easy solution to avoid having to address the real issue – whether that is a lack of effort or a lack of talent – or to enjoy the sense of belonging to an elite group, and having the false idea that it must work if elite athletes are wearing it," Forzoni said.

A spokeswoman for Power Balance was unable to provide any evidence showing how the wristbands helped athletes. "Unfortunately, there have not been any scientific studies," she said. "The use of frequencies to enhance fitness and wellbeing goes back to ancient Chinese philosophy. Many people are sceptical about the product as there isn't any research to back it up, but if you've seen it working and can feel it working then you can't deny what it's doing."

To persuade prospective customers to buy the bands, Power Balance suggests taking the test of standing on one leg with your arms out to the sides, with a friend pushing down on one arm. The first time, when you are not wearing one of the wristbands, they say you are likely to topple over. The second time, when you have slipped one of the bands around your wrist, the suggestion is that you will have much greater strength and balance, and it is much more likely that you will be able to stay upright.

Rugby is not a sport that you would associate with New Age thinking, and Huw Davies, the head of strength and conditioning at Wasps, said that a number of the players had hoped that the bands would be "a load of crap".

"Some of the players almost wished that the bands would not work, they hoped that it was just pseudoscience, but then they saw their results in the gym and they were much better," Davies said. "The bands have helped a number of players with their rehabilitation from injury. It seems as though there is something to it. Six of our players use the bands in training, and two or three of the guys wear them during matches. Some of the players have reported experiencing better balance, strength and flexibility when wearing the band.

"To the sceptics, I would say, 'keep an open mind'."