Post Marathon Allergies: More Common than you Think

As almost 40,000 runners get set to take part in this year's London Marathon, a new study has found that one in three will suffer from allergies after the event. -sciencedaily

As the article points out, this was London, host of the 2012 Olympic games.

"The Olympics are taking place during the peak grass-pollen period," she says, "so, if almost three out of ten people are potentially allergic to this common aeroallergen, it is a priority to have Olympic athletes tested before the games so an appropriate treatment regime can be put in place."