Abstract Objectives: Completing 100 marathons defines a multi-marathoner. The aim of this study was to document the sport of multi-marathoning and to report on the demographics, culture, and participatory nature of the sport. Methods: A survey was distributed globally to the sports participants. All the major national and international multi-marathon clubs supported the survey distribution via their closed social media and email groups. The survey was fully anonymous and online. Results: The survey attracted 830 respondents from 40 countries, with an average marathon completion count of 146 per respondent. 60% of respondents were men, with a respondent's average age of over 50 years. Social life and travel superseded competitiveness as the main motivation as participants age. 57% of respondents had at least one contravention to a pre-participation screening questionnaire and 67% took pain relief medication around events. 93% of respondents reported that multi-marathoning was good for their mental health. Discussion: Multi-marathoning facilitates the older athlete, but there is a significant gender imbalance in participation. Long-term health damage potential is significant, and health awareness requires addressing by governing bodies, event facilitators and participants alike. Multi-marathoners should use available information from modern equipment to inform their health status and to optimise training. Conclusion: Recommendations from the study include implementing women-specific enhancements to events, race directors having adequately resourced health plans at events, and participants taking accountability for their own health by including proactive regular health management before and during their participation in the sport.

The authors have declared no competing interest.

This study did not receive any funding

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Faculty of Health Sciences Research Ethics Committee, Trinity College Dublin APPROVED

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