Ever experience thigh rubbing so painful your legs feel like they’ve brushed against a cheese grater? Or cross a finish line, realising that the spectacle of your blood-streaked shirt is eliciting horror from spectators? Chafing, a runner’s rite of passage, is the result of friction that occurs when skin rubs against itself or clothing. As anyone who has endured an excruciating post-run shower on freshly grazed skin knows, prevention is all-important. - Stephen Varanko III