Former world 3000m steeplechase champion Marta Dominguez announced Wednesday that she is to trade in the track for road running, with an eye on competing in marathons. The 36-year-old, crowned world champion in Berlin in 2009, could only finish 12th in the steeplechase at this summer\'s London Olympics and said she could no longer run the event, describing it as \"too traumatic\". \"The idea is to do road races,\" Dominguez said. \"I\'m thinking about the marathon, but you have to see how the head and body respond. \"It\'s a very demanding discipline and you have to progress little by little.\" Dominguez, cleared of doping allegations in 2011, also won world silvers in the 5000m in 2003 and 2001.