Nike's invention contains a curved carbon plate built into the sole, which insiders claim "acts like a spring and propels the runner forward", according to a Times report.
Nike has also developed a unique foam which is used in the sole, something it will not sell to other companies.
The Vaporfly, worn by the fastest ever marathon runners, was blasted by critics who suggest that the then-prototype shoe determined not only the marathoners the United States sent to Rio for the 2016 Olympics but also who medalled in those games.
The Alphafly has faced similar criticism about the shoe not being readily available to all runners.
The Nike Vaporfly shoes worn by Eliud Kipchoge. Photo / Photosport
In a bid to change this, Nike has confirmed to Runner's World that every athlete running in this week's trials has the option of receiving a pair after picking up their bib.
The Alphafly is permissible for use in the trials as a prototype under the new World Athletics rules.
Prototypes may be used only until April 30, 2020, after which time a shoe must have been available for purchase for at least four months.
The only requirements for current road shoes is that the stack height must be no thicker than 40mm and that it may contain at most one plate, whether made from carbon fibre or any other material.
When it announced the Alphafly, Nike said a limited number will be available to Nike Plus members on the day of the Olympic Marathon Trials on February 29.
