Influence of Vaporfly shoe on sub-2 hour marathon and other top running performances

In 2019, Eliud Chipgoke ran a sub-two hour marathon in an unofficial race wearing last-generation shoes. The legitimacy of this feat was naturally questioned due to unusual racing conditions and suspicions of technological doping. In this work, we assess the likelihood of a sub-two hour marathon in an official race, and the potential influence of Vaporfly shoes, by studying the evolution of running top performances from 2001 to 2019 for distances ranging from 10k to marathon. The analysis is performed using extreme value theory, a field of statistics dealing with analysis of records. We find a significant evidence of technological doping with a 12% increase of the probability that a new world record for marathon-man discipline is set in 2021. However, results suggest that achieving a sub-two hour marathon in an official event in 2021 is still very unlikely, and exceeds 10% probability only by 2025.