We describe the best organizational practices, ceremonies, and rituals of mass participation sports events. In addition to participant observation of endurance races in distance running, triathlon, cycling, swimming, and cross-country skiing between 2003 and 2019, statistical and document analysis was used as the research methodology. Special focus was placed on triathlon in Europe. We argue that the phenomenon of mass participation sports is a consequence of the Expressive model of sports (EMS) as a social construct shared by the community. We explain how the EMS is implemented in the organization of events through rituals, conventions, and institutions. Firstly, within the EMS, the race finish is recognized as an achievement by the organizers and the participant’s community. Secondly, the EMS focuses on ordinary, non-elite amateurs as main event participants. This means an open entry to participation, with no selection by skill level; permissive time limits; equal distances, entry fees, and service levels for both elite and non-elite athletes; a joint festival and event venue; competition schedule comfortable for amateurs (non-elite races on the weekend). Thirdly, the EMS revises the linear ranking of competitions through a new hierarchy model, an age-weighted presentation of results, and an inclusive celebration ritual. This includes the grouping of athletes into ordinary amateurs with no reward and elite/professionals, who compete for absolute an ranking and/or prizes, a broad division of amateurs by age groups (95–99, 90–94, 85–89 and down to 20–24, 15–19) and the celebration of the oldest athletes and last finishers. The theoretical framework combines the insights from the civilization process, evolutionary and symbolic anthropology. Since endurance races are seen as rites of passage and liminal processes, we emphasize the importance of rituals as a means of a reconciliation of communitas.