Vitali Klitschko's Secret Weapon -- Urine Trouble Now 

Wait 'til R. Kelly hears about this.

This is heavyweight champ Vitali Klitschko admitting he uses his infant son's used wet diapers to keep the swelling down after his fights. "I wrap nappies filled with my 3-year-old son Max's wee around my fists," he tells German newspaper Bild. The urine, says Vitali, is "pure" and "doesn't smell."

Well, he is a doctor ... no, seriously, he has a PhD.