I dont think so, not in the long run anyway, it probably will while the olympics are on but then participation levels will slowly drop, theres a better chance if Britain win loads of medals

Running for an hour is about a 1 half marathon = 21.097494 kilometers.
A half marathon is a road running event of 21,097.5 meters, or 13+7⁄64 miles, about 13.1 miles. It is half the distance of a marathon and usually run on roads. It is a popular race for intermediate runners, long enough to be a serious challenge but not requiring the level of training of a marathon. In consequence, many towns and cities hold annual all-comers half marathon races through their streets. It is also common for a half marathon event to be held concurrently with a marathon, using almost the same course with an early finish. So yeah its hard.