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Exercise and immune function: effect of ageing and nutrition

Published online by Cambridge University Press:  28 February 2007

Bente Klarlund Pedersen*
Affiliation:
The Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, 2200 Copenhagen N, Denmark
Helle Bruunsgaard
Affiliation:
The Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, 2200 Copenhagen N, Denmark
Marianne Jensen
Affiliation:
The Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, 2200 Copenhagen N, Denmark
Karen Krzywkowski
Affiliation:
The Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, 2200 Copenhagen N, Denmark
Kenneth Ostrowski
Affiliation:
The Copenhagen Muscle Research Centre and Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, 2200 Copenhagen N, Denmark
*
*Corresponding Author: Dr Bente Klarlund Pedersen, fax +45 3545 6648, email bkp@rh.dk
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Abstract

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Strenuous exercise is followed by lymphopenia, neutrophilia, impaired natural immunity, decreased lymphocyte proliferative responses to mitogens, a low level of secretory immunoglobulin A in saliva, but high circulating levels of pro- and anti-inflammatory cytokines. These exercise-induced immune changes may provide the physiological basis of altered resistance to infections. The mechanisms underlying exercise-induced immune changes are multifactorial and include neuroendocrinological and metabolic mechanisms. Nutritional supplementation with glutamine abolishes the exercise-induced decline in plasma glutamine, but does not influence post-exercise immune impairment. However, carbohydrate loading diminishes most exercise effects of cytokines, lymphocyte and neutrophils. The diminished neutrophilia and elastase (EC 3.4.21.37) responses to eccentric exercise in elderly subjects were enhanced to levels comparable with those of young subjects by fish oil or vitamin E supplements. However, although vitamin C supplementation may diminish the risk of contracting an infection after strenuous exercise, it is not obvious that this effect is linked to an effect of vitamin C on exercise-induced immune changes. In conclusion, it is premature to make recommendations regarding nutritional supplementation to avoid post-exercise impairment of the immune system.

Type
Symposium on ’Nutrition, infection and immunity‘
Copyright
Copyright © The Nutrition Society 1999

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