title: Post-160-km race illness rates and decreases in granulocyte respiratory burst and salivary IgA output are not countered by quercetin ingestion.
abstract: This study measured the influence of the flavonoid quercetin on immune changes and incidence rates of upper respiratory tract infections in ultramarathoners competing in the 160-km Western States Endurance Run. Sixty-three runners were randomized to quercetin and placebo groups, and under double-blinded methods ingested 1000 mg/day quercetin for 3 wks before, during, and 2 wks after the race. Thirty-nine of the 63 subjects (n = 18 for quercetin, n = 21 for placebo) finished the race and provided blood and saliva samples the morning before the race and 15 - 30 min postrace. Upper respiratory tract infections were assessed during the week before and the 2-wk period after the race using an illness symptom checklist. Race times did not differ significantly between quercetin and placebo groups. Significant pre- to postrace decreases were measured for natural killer cells (43 %), granulocyte respiratory burst activity (55 %), and salivary IgA output (48 %), and increases for neutrophil (288 %) and monocyte (211 %) cell counts, with no significant group differences. Postrace illness rates did not differ between groups. In conclusion, quercetin supplementation for 3 wks before and 2 wks after the Western States Endurance Run had no effect on illness rates, perturbations in leukocyte subset counts, or decreases in granulocyte respiratory burst activity and salivary IgA.
authors.affiliation: Department of Biology, Appalachian State University, Boone, North Carolina 28608, United States. hensonda@appstate.edu
authors.forename: D
authors.initials: D
authors.lastname: Henson
authors.forename: D
authors.initials: D
authors.lastname: Nieman
authors.forename: J M
authors.initials: JM
authors.lastname: Davis
authors.forename: C
authors.initials: C
authors.lastname: Dumke
authors.forename: S
authors.initials: S
authors.lastname: Gross
authors.forename: A
authors.initials: A
authors.lastname: Murphy
authors.forename: M
authors.initials: M
authors.lastname: Carmichael
authors.forename: D P
authors.initials: DP
authors.lastname: Jenkins
authors.forename: J
authors.initials: J
authors.lastname: Quindry
authors.forename: S
authors.initials: S
authors.lastname: McAnulty
authors.forename: L
authors.initials: L
authors.lastname: McAnulty
authors.forename: A
authors.initials: A
authors.lastname: Utter
authors.forename: E
authors.initials: E
authors.lastname: Mayer
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006098:Granulocytes / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011794:Quercetin / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D016897:Respiratory Burst / Q000187:drug effects* / Q000502:physiology; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D012420:Running / Q000502:physiology; D012469:Salivary Glands / Q000378:metabolism; D013177:Sports
chemical_list: D000975:Antioxidants; D007070:Immunoglobulin A; D011794:Quercetin