Adidas, its bigger rival Nike and other sports brands, have been locked in a "supershoe" war for years, since the first running shoes containing a thick, shock-absorbing foam and carbon fibre plate helping athletes run more efficiently, were released. At $500 a pair, the Adizero Adios Pro Evo 1 cost $225 more than Nike's equivalent Alphafly 2, raising the question of how many amateur runners will swallow the extra cost. "The price tag is just insane," said Harry Swinhoe, founder of Grove Lane Runners, an amateur running club in southeast London. "This is a shoe optimized for speed, versus durability," Adidas said. Assefa broke the world record by more than 2 minutes to finish in 2 hours, 11 minutes and 53 seconds.

---

Persons: Ethiopia's Tigist, Harry Swinhoe, Bjorn Gulden, Assefa, Helen Reid, Sharon Singleton Organizations: Adidas, Nike, Evo, Thomson Locations: Berlin, Lane, London