Adam Peaty’s early swimming instructors were “gobsmacked” by his talent as a child.The staff at Uttoexeter Leisure Centre always knew their former charge was going to be special and were beaming with pride on Monday morning as Peaty made British swimming history by defending his Olympic title.The 26-year-old was in a class apart as he powered to victory in the 100 metres breaststroke at Tokyo 2020, following up his triumph from Rio five years ago.