Beta-glucan, immune function, and upper respiratory tract infections in athletes.
OBJECTIVE
This study investigated the effects of oat beta-glucan (BG) supplementation on chronic resting immunity, exercise-induced changes in immune function, and self-reported upper respiratory tract infection (URTI) incidence in human endurance athletes.


METHODS
Trained male cyclists were randomized to BG (N = 19) or placebo (P; N = 17) groups and under double-blind procedures received BG (5.6 g x d(-1)) or P beverage supplements for 2 wk before, during, and 1 d after a 3-d period in which subjects cycled for 3 h x d(-1) at approximately 57% maximal watts. URTI symptoms were monitored during BG supplementation and for 2 wk afterward. Blood samples were collected before and after 2 wk of supplementation (both samples, 8:00 a.m.), immediately after the 3-h exercise bout on day 3 (6:00 p.m.), and 14 h after exercise (8:00 a.m.) and were assayed for natural killer cell activity (NKCA), polymorphonuclear respiratory burst activity (PMN-RBA), phytohemagglutinin-stimulated lymphocyte proliferation (PHA-LP), plasma interleukin 6 (IL-6), IL-10, IL-1 receptor agonist (IL-1ra), and IL-8, and blood leukocyte IL-10, IL-8, and IL-1ra mRNA expression.


RESULTS
Chronic resting levels and exercise-induced changes in NKCA, PMN-RBA, PHA-LP, plasma cytokines, and blood leukocyte cytokine mRNA did not differ significantly between BG and P groups. URTI incidence during the 2-wk postexercise period did not differ significantly between groups.


CONCLUSIONS
An 18-d period of BG versus P ingestion did not alter chronic resting or exercise-induced changes in immune function or URTI incidence in cyclists during the 2-wk period after an intensified exercise.
Nieman
David C
DC
Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC 28608, USA. niemandc@appstate.edu
Henson
Dru A
DA
McMahon
Mary
M
Wrieden
Jenna L
JL
Davis
J Mark
JM
Murphy
E Angela
EA
Gross
Sarah J
SJ
McAnulty
Lisa S
LS
Dumke
Charles L
CL
D019587:Dietary Supplements; D004311:Double-Blind Method; D005080:Exercise Test; D006801:Humans; D007107:Immune System / Q000187:drug effects*; D008297:Male; D005082:Physical Exertion / Q000502:physiology; D012141:Respiratory Tract Infections / Q000188:drug therapy / Q000453:epidemiology / Q000276:immunology*; D013177:Sports; D047071:beta-Glucans / Q000008:administration & dosage / Q000276:immunology*
D047071:beta-Glucans