Training-related factors, average wet-bulb temperature, females and older age are risk factors for not finishing an ultramarathon

Posted on September 02, 2021

Participation in mass community-based endurance running events is growing, as awareness increases around the numerous health-benefits of regular exercise. In particular, participation in marathon and ultra-marathon running events is increasing, which, although supported in principle, comes with the potential of more medical events occurring during and after the races. Medical events/encounters however, are not the only “adverse events” that can occur. Starting but not finishing a marathon or ultra-marathon is a common occurrence, which places a burden on the runner and the race organisers. Therefore, knowing the risk factors associated with not finishing, could assist participants to better prepare for their race, and improve their chances of completing the distance. A study published this year involving SEMLI researchers aimed to identify risk factors associated with not finishing an ultramarathon (56km) road running race, using a pre-race medical screening questionnaire and race day factors. This study showed that training-related factors predominantly were associated with an increased risk of a participant not finishing. These included years of running, less previous race experience, less training/racing per week, lower average weekly training distance, and slower race vs. training speed. Previous research has shown that females and older-aged participants are at increased risk of medical complications, and this study shows that these same groups could also be at higher risk of not finishing an ultra-marathon race. This is important information, because these sorts of races are attracting more women and older participants, so this could have implications on the planning of medical care at these races.  This study also looked at environmental factors, and found that average wet bulb temperature was also associated with not finishing. These results may not only assist runners and coaches in race preparation, but may also have clinical implications for the medical planning prior to races.


Lead author, Dr Nicola Sewry, is currently a Lecturer at the Sport, Exercise Medicine and Lifestyle Institute (SEMLI), where she is managing the SAFER International Million+ Athlete research Program (IMAP). Her research is focusing on quantifying the extent of medical encounters and the risk factors associated with medical encounters during mass community-based endurance sport events, with the aim of making these events safer for all participants.


Risk factors for not finishing an ultramarathon: 4-year study in 23996 race starters, SAFER XXI

J Sports Med Phys Fitness. 2021 Apr 19

Sewry N, Schwellnus M, Borjesson M, Swanevelder S, Jordaan E

Published by Jill Borresen

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