http://www.yomiuri.co.jp/sports/news/20100802-OYT1T00642.htm?from=main3translated and edited by Brett LarnerThe mass marathon boom is overheating. Races everywhere are selling out within a matter of hours. Tokyo's "Runner's Paradise," the Imperial Palace loop, is packed solid with runners even at the peak of summer heat. On Aug. 1 the spark that set off the wildfire, the Tokyo Marathon, opened applications for next year's edition scheduled for Feb. 27. Applications exceeded the field size of 32,000 in less than 48 hours. Organizers expect to measure the total number of applicants in the hundreds of thousands.
The trend has spread to other races. The Nov. 28 Tsukuba Marathon, with a field limit of 12,000, sold out in 13 hours. Last year's race took 3 days to reach the limit. The 8,000-limit Nagano Marathon this past April 18 sold out in 5 and 1/2 hours. The Teganuma Eco Half-Marathon on Oct. 31 filled all 7,000 spots in 8 hours 20 minutes after taking 2 days la…