Carbohydrate affects natural killer cell redistribution but not activity after running.
This randomized, double-blind, placebo-controlled study was designed to determine the influence of carbohydrate supplementation on the natural killer cell response to 2.5 h of high-intensity running (76.7 +/- 0.4% VO2max). Thirty experienced marathon runners (VO2max 53.4 +/- 1.0 mL x kg[-1] x min[-1], age 41.5 +/- 1.4 yr) were randomized into carbohydrate supplement (N = 17) and placebo (N = 13) groups. Subjects rested for 10-15 min before a blood sample at 0715, and then ingested 0.75 L of carbohydrate beverage (Gatorade) or placebo. At 0730, subjects began running at 75-80% VO2max for 2.5 h and drank 0.25 L of carbohydrate or placebo fluid every 15 min. Immediately after the 2.5 h run (1000), another blood sample was taken, followed by 1.5 h, 3 h, and 6-h recovery samples. Carbohydrate supplementation versus placebo had a significant effect on the pattern of change in glucose, cortisol, and the blood concentration of natural killer cells ([F (4,25) = 3.79, P = 0.015], but not natural killer cell activity following 2.5 h of intensive running.
Nieman
D C
DC
Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC 28608, USA. niemandc@appstate.edu
Henson
D A
DA
Garner
E B
EB
Butterworth
D E
DE
Warren
B J
BJ
Utter
A
A
Davis
J M
JM
Fagoaga
O R
OR
Nehlsen-Cannarella
S L
SL
D000328:Adult; D000704:Analysis of Variance; D001786:Blood Glucose / Q000378:metabolism; D002395:Catecholamines / Q000097:blood; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010919:Placebos; D012420:Running / Q000502:physiology*
D001786:Blood Glucose; D002395:Catecholamines; D004040:Dietary Carbohydrates; D010919:Placebos; D006854:Hydrocortisone