http://www.bbc.co.uk/news/health-18863293
Consumers could be wasting their money on sports drinks, protein shakes and high-end trainers, according to a new joint investigation by BBC Panorama and the British Medical Journal.
The investigation into the performance-enhancing claims of some popular sports products found "a striking lack of evidence" to back them up.
A team at Oxford University examined 431 claims in 104 sport product adverts and found a "worrying" lack of high-quality research, calling for better studies to help inform consumers.
Dr Carl Heneghan of the Oxford University Centre for Evidence-Based Medicine led the independent research into the claims made by the makers of sports drinks, protein shakes and trainers.
In the case of Lucozade Sport, the UK's best-selling sports drink, their advert says it is "an isotonic performance fuel to take you faster, stronger, for longer".
'Minuscule effect'
Dr Heneghan and his team asked manufacturer GlaxoSmithKline (GSK) for details of the science behind their claims and were given what he said scientists call a "data dump" - 40 years' worth of Lucozade sports research which included 176 studies.
Dr Heneghan said the mountain of data included 101 trials that the Oxford team were able to examine before concluding: "In this case, the quality of the evidence is poor, the size of the effect is often minuscule and it certainly doesn't apply to the population at large who are buying these products.