(Right) Kartik Karkera during the 21st edition of the Tata Mumbai Marathon; Sabastian Sawe holding up the Adidas Adizero Adios Pro Evo 3 after running the London Marathon in under two hours. (PTI/AP Photo) By Kartik Karkera The difference between an elite international athlete like Sabastian Sawe and an athlete like me is that he uses a prototype or development shoe made specifically for him by the brand (Adidas), which sponsors him. But I wear a pair of shoe that can be bought in the market. For the marathons in Mumbai and Delhi , I wore the ASICS Metaspeed Sky Tokyo. Its price range starts from Rs 25,000, but it is not the latest version. For an athlete like Sawe, or another elite athlete with a shoe sponsor, the shoe size won’t be like a standard UK size 8 or 9 but will be the one that fits their leg perfectly. These prototype shoes are sometimes not released in the market at all. Not accessible At the Bengaluru 10K, I saw international athletes wearing a development shoe of ASICS — MS5 Type-P.…