title: Nausea is associated with endotoxemia during a 161-km ultramarathon.
abstract: This study explored possible contributing factors to gastrointestinal distress, including endotoxemia, hyperthermia, dehydration and nutrition, during a 161-km ultramarathon. Thirty runners participated in the study and 20 finished the race. At three checkpoints and the finish, runners were interviewed to assess the incidence and severity of 12 gastrointestinal symptoms and to determine dietary intake. Core temperature was measured at the same locations. Runners were weighed pre-race, at the three checkpoints and the finish to monitor hydration status. Blood markers for endotoxemia (sCD14) and inflammation (interleukin-6 and C-reactive protein) were measured pre- and post-race. Gastrointestinal symptoms were experienced by most runners (80%), with nausea being the most common complaint (60%). Runners with nausea experienced significantly greater (P = 0.02) endotoxemia than those without nausea (sCD14 mean increase 0.7 versus 0.5 µg · mL(-1)). There was a significant positive correlation (r = 0.652, P = 0.005) between nausea severity and endotoxemia level. Inflammatory response, core temperature, hydration level and race diet were similar between runners with and without nausea. This study links endotoxemia to nausea in ultramarathon runners. Other possible contributing factors to nausea such as hyperthermia, dehydration and nutrition did not appear to play a role in the symptomatic runners in this study.
authors.affiliation: a Health Sciences Department , Gettysburg College , Gettysburg , PA , USA.
authors.forename: Kristin J
authors.initials: KJ
authors.lastname: Stuempfle
authors.affiliation: b Department of Kinesiology , San Francisco State University , San Francisco , CA , USA.
authors.forename: Taylor
authors.initials: T
authors.lastname: Valentino
authors.affiliation: c Exercise Science, School of Health Science , Oakland University , Rochester , MI , USA.
authors.forename: Tamara
authors.initials: T
authors.lastname: Hew-Butler
authors.affiliation: d Department of Medicine, School of Medicine , University of California at San Francisco , San Francisco , CA , USA.
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Hecht
authors.affiliation: e Department of Physical Medicine & Rehabilitation, Department of Veterans Affairs , Northern California Health Care System, and University of California Davis Medical Center , Sacramento , CA , USA.
authors.forename: Martin D
authors.initials: MD
authors.lastname: Hoffman
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001831:Body Temperature; D002097:C-Reactive Protein / Q000378:metabolism; D003681:Dehydration / Q000150:complications; D004032:Diet; D019446:Endotoxemia / Q000150:complications*; D005260:Female; D005334:Fever / Q000150:complications; D005767:Gastrointestinal Diseases / Q000209:etiology; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D018950:Lipopolysaccharide Receptors / Q000097:blood; D008297:Male; D009325:Nausea / Q000209:etiology*; D010807:Physical Endurance / Q000502:physiology*; D012420:Running / Q000502:physiology*; D055815:Young Adult
chemical_list: D015850:Interleukin-6; D018950:Lipopolysaccharide Receptors; D002097:C-Reactive Protein
keywords: Gastrointestinal distress; bacterial translocation; ultramarathon runners