Gastrointestinal distress is common during a 161-km ultramarathon

Abstract

This study examined the incidence, severity, and timing of gastrointestinal (GI) symptoms in finishers and non-finishers of the 161-km Western States Endurance Run. A total of 272 runners (71.0% of starters) completed a post-race questionnaire that assessed the incidence and severity (none = 0, mild = 1, moderate = 2, severe = 3, very severe = 4) of 12 upper (reflux/heartburn, belching, stomach bloating, stomach cramps/pain, nausea, vomiting) and lower (intestinal cramps/pain, flatulence, side ache/stitch, urge to defecate, loose stool/diarrhoea, intestinal bleeding/bloody faeces) GI symptoms experienced during each of four race segments. GI symptoms were experienced by most runners (96.0%). Flatulence (65.9% frequency, mean value 1.0, s = 0.6 severity), belching (61.3% frequency, mean value 1.0, s = 0.6 severity), and nausea (60.3% frequency, mean value 1.0, s = 0.7 severity) were the most common symptoms. Among race finishers, 43.9% reported that GI symptoms affected their race performance, with nausea being the most common symptom (86.0%). Among race non-finishers, 35.6% reported that GI symptoms were a reason for dropping out of the race, with nausea being the most common symptom (90.5%). For both finishers and non-finishers, nausea was greatest during the most challenging and hottest part of the race. GI symptoms are very common during ultramarathon running, and in particular, nausea is the most common complaint for finishers and non-finishers.

Keywords:

• ultramarathon running
• gastrointestinal symptoms
• nausea

Acknowledgments

This study was supported with resources and the use of facilities at the VA Northern California Health Care System. We thank the following individuals for their assistance: Ali Alvandi, Dr Kim Corrigan, Dr Kevin Fogard, Dr Tracy Høeg, Dr Mark Kasmer, Rachel Lord, Dr Christine Mathiesen, Dr Vanessa McGowan, Kevin Mullins, Dr Ken Onishi, Dr David Oxborough, Dr David Paris, Professor John Somauroo, Carol Steinbrecher, Steve Steinbrecher, Mike Stembridge, Taylor Valentino, and Lisa Weiss. The contents reported here do not represent the views of the Department of Veterans Affairs or the United States Government.

Additional information

Funding

This study was supported by the Western States Endurance Run Foundation.