THE WORLD Anti-Doping Agency (Wada) has vowed to investigate claims top ski jumpers are manipulating the size of their crotch areas in order to get one over their rivals.

Claims first surfaced in the German newspaper Bild last month that athletes were injecting substances like hyaluronic acid directly into their penises in order to boost their size and merit a bigger ski suit — which helps aerodynamics.

Wada director general Olivier Niggli said at a press conference in Milan: “I am not aware of the details of ski jumping, and how that could improve performance.

“If anything was to come to the surface, we would look at it and see if it is doping related. We don’t address other (non-doping) means of enhancing performance.”

Ski jumpers have strongly denied such a practice exists, and no athlete has been either accused or found guilty of such a practice.

However, ski jumping teams have long sought to gain a competitive advantage over rivals by making minor changes to their jumping suits.

Last month, a number of members of the Norwegian team were suspended after being caught on video adding illegal stitching into the crotch area of their suits during last year’s World Championship.