From Prof Ross Tucker (ZA) post a month ago.
There’s reason to think that the likeliest tactic this year will be a shoe that changes the relationship between those three factors I mentioned earlier. A shoe with springs, for instance, would allow a runner to go the same speed using less energy. Ergo, they could go faster before a potential limit is reached.
Indeed, I suspect this shoe already exists, has been used by a few runners in the last year (Rupp, Bekele), and will be used by another great marathon runner, Kenenisa Bekele, in a marathon in Dubai this coming Friday, so keep an eye out for a potential world record there, and a hint of what may be to come.