A bracelet worn by high profile sports stars that claims to improve athletic performance has been exposed as a sham by the consumer watchdog.

The Australian Competition and Consumer Commission (ACCC) has ordered Power Balance Australia to refund all customers who feel they were misled by the supposed benefits of Power Balance bracelets.

The wristbands were touted as providing better balance, strength and flexibility by working with the wearer's "natural energy field".

English cricketers Kevin Pietersen and Andrew Strauss, AFL bad boy Brendan Fevola, St Kilda captain Nick Riewoldt and NRL star Benji Marshall have all been known to wear the bracelets.