US-American professional IRONMAN® triathletes dominate participation but not performance in IRONMAN® races – an internet-based cross-sectional study using a machine learning approach (Preprint)

Abstract

Since the first edition of IRONMAN® Hawaii in 1981, the number of races and finishers in the IRONMAN® format has increased considerably. Scientific literature has provided many insights into this specific sport discipline. However, we have no knowledge of where the fastest professional IRONMAN® triathletes originate and where the fastest IRONMAN® race courses take place.

The aim of the present study was to investigate where in the world the fastest IRONMAN® race courses for professional IRONMAN® triathletes are.

Data of all professional female and male IRONMAN® triathletes competing between 2002 and 2022 in all official IRONMAN® races were collected. A total of 6,954 finishers´ records (2,788 women and 4,166 men) from 68 different countries participating in 56 different event locations were considered. Data were analyzed using machine learning (ML) regression models. The models considered gender, country of origin, and event location as independent variables to predict the final race time. Five different algorithms (Random Forest Regressor, XG Boost Regressor, Ada Boost Regressor, Cat Boot Regressor, and Decision Tree Regressor) were examined.

The race site was the most important variable for the Random Forest Regressor model, while for the other four models, gender was the most important variable. A decision tree algorithm, trained with data from 2002 to 2022, showed that the fastest overall IRONMAN® race times of 08:38:48 h:min:s will be obtained in IRONMAN® Hawaii, IRONMAN® Florida, IRONMAN® Austria, IRONMAN® France, IRONMAN® Wisconsin, IRONMAN® Lanzarote or IRONMAN® Texas by male professional IRONMAN® triathletes originating from any other country than USA, Germany or Canada. Most of the professional IRONMAN® triathletes originated from the USA (1,786), followed by athletes from Germany (674) and Canada (427). Most athletes competed in IRONMAN® Hawaii (926), followed by IRONMAN® Florida (564) and IRONMAN® Austria (454).

The fastest IRONMAN® race courses for professional IRONMAN® triathletes are predominately located in the USA. Most of the professional IRONMAN® triathletes originated from the USA. The fastest IRONMAN® race times were achieved by male professional IRONMAN® triathletes originating from any other country than USA, Germany, or Canada. These insights are useful for athletes and coaches in planning their professional IRONMAN® career.