A STACK of Olympic and possibly world records will be broken on the Tokyo track over the next two weeks, but such has been the incredible impact of shoe technology on performance lately, that nobody quite knows what constitutes great any more. It used to be the case the world records on the road and track were edged down by fractions of a second, often untouched for years at a time, before the next generation shaved a couple of hundredths and were rightly feted.
