Significant rule changes for footwear have been imposed by World Athletics, who have outlawed some variations of Nike's Vaporfly shoes.
Strict limits will also be imposed on technology for shoes used in elite competition in the future.
Soles can no longer be thicker than 40mm and not contain more than a single rigid, embedded plate.
Eliud Kipchoge ran the first sub-two hour marathon while fellow Kenyan Brigid Kosgei broke the women's marathon world record using the Vaporfly shoes, which contain triple carbon plates inside thick, ultra-compressed foam.
The design improved running economy by up to four per cent, Nike claimed.
Form April 30, shoes used by athletes must have been available to the public for four months.
“If a shoe is not openly available to all then it will be deemed a prototype and use of it in competition will not be permitted,” the statement from World Athletics said.
The Tokyo Olympics open in just under six months.
“As we enter the Olympic year, we don’t believe we can rule out shoes that have been generally available for a considerable period of time,” World Athletics president Sebastian Coe said, “but we can draw a line by prohibiting the use of shoes that go further than what is currently on the market while we investigate further.
“I believe these new rules strike the right balance by offering certainty to athletes and manufacturers as they prepare for the Tokyo 2020 Olympic Games.”
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