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Flow Cytometric Analysis of Natural Killer Cell Lytic Activity in Human Whole Blood
Published on: March 17, 2017
Carbohydrate affects natural killer cell redistribution but not activity after running
D C Nieman1, D A Henson, E B Garner
1Department of Health, Leisure, and Exercise Science, Appalachian State University, Boone, NC 28608, USA. niemandc@appstate.edu
Medicine and Science in Sports and Exercise
|November 5, 1997
Summary
Carbohydrate supplementation significantly altered glucose, cortisol, and natural killer cell levels during prolonged high-intensity running. This suggests carbohydrates impact immune responses in endurance athletes.
Area of Science:
- Exercise Physiology
- Immunology
- Sports Nutrition
Background:
- Endurance exercise can suppress immune function.
- Natural killer (NK) cells play a role in immune surveillance.
- The impact of carbohydrate intake on NK cell response during intense exercise is not fully understood.
Purpose of the Study:
- To investigate the effect of carbohydrate supplementation on NK cell response during 2.5 hours of high-intensity running.
- To examine the influence of carbohydrates on hormonal and metabolic markers alongside NK cell concentration.
Main Methods:
- A randomized, double-blind, placebo-controlled trial involving 30 experienced marathon runners.
- Participants received either a carbohydrate beverage or a placebo during 2.5 hours of running at 75-80% VO2max.
- Blood samples were collected pre-exercise, immediately post-exercise, and at 1.5, 3, and 6 hours into recovery.
Main Results:
- Carbohydrate supplementation significantly affected the pattern of change in blood glucose, cortisol, and NK cell concentration.
- No significant difference was observed in NK cell activity between the groups.
- The study found a significant effect on the concentration of NK cells ([F (4,25) = 3.79, P = 0.015]).
Conclusions:
- Carbohydrate intake during prolonged high-intensity exercise modulates NK cell concentration and associated metabolic and hormonal responses.
- While NK cell concentration is affected, NK cell activity may not be significantly altered by carbohydrate supplementation in this context.
- Findings suggest a role for carbohydrate strategies in managing immune responses during intense endurance events.
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