The question of whether transgender athletes should be allowed to compete in women’s sport is one that has been floating around for a few years now but, with the recent NCAA victory of Lia Thomas in the US, it has been thrown into the limelight again. Complaints have been made from numerous fellow swimmers as to why Thomas – who has been undergoing hormone replacement therapy for two and a half years – was allowed to compete. In her column this morning Sonia O’Sullivan lays out her case for why transgender athletes should not be allowed to compete in women’s sport as they will always have a biological advantage. “It’s not just about setting rules around testosterone levels, it’s also the physical size and ability of the per …