Elsevier

Nutrition

Volume 13, Issues 7–8, July–August 1997, Pages 738-742
Nutrition

Symposium proceedings
The effects of oral glutamine supplementation on athletes after prolonged, exhaustive exercise

https://doi.org/10.1016/S0899-9007(97)83036-5Get rights and content

Abstract

Athletes undergoing intense, prolonged training or participating in endurance races suffer an increased risk of infection due to apparent immunosuppression. Glutamine is an important fuel for some cells of the immune system and may have specific immunostimulatory effects. The plasma glutamine concentration is lower after prolonged, exhaustive exercise: this may contribute to impairment of the immune system at a time when the athlete may be exposed to opportunistic infections. The effects of feeding glutamine was investigated both at rest in sedentary controls and after exhaustive exercise in middle-distance, marathon and ultra-marathon runners, and elite rowers, in training and competition. Questionnaires established the incidence of infection for 7 d after exercise: infection levels were highest in marathon and ultra-marathon runners, and in elite male rowers after intensive training. Plasma glutamine levels were decreased by ∼20% 1 h after marathon running. A marked increase in numbers of white blood cells occurred immediately after exhaustive exercise, followed by a decrease in the numbers of lymphocytes. The provision of oral glutamine after exercise appeared to have a beneficial effect on the level of subsequent infections. In addition, the ratio of T-helper/T-suppressor cells appeared to be increased in samples from those who received glutamine, compared with placebo.

References (27)

  • EA Newsholme et al.

    Glutamine metabolism in lymphocytes: its biochemical, physiological and clinical importance

    Q J Exp Physiol

    (1985)
  • PC Calder

    Requirement for both glutamine and arginine by proliferating lymphocytes

    Proc Nutr Soc

    (1995)
  • H Powell et al.

    Growth hormone suppression and glutamine flux associated with cardiac surgery

    Clin Physiol

    (1994)
  • Cited by (117)

    • Potential therapeutic implications of ergogenic compounds on pathophysiology induced by traumatic brain injury: A narrative review

      2019, Life Sciences
      Citation Excerpt :

      In this regard, glutathione peroxidase neutralizes hydrogen peroxide, being the best known pathway by which glutamine controls ROS levels [206]. In physical exercises, for instance, glutamine supplementation is reported to occur during recovery after marathon running [207,208]. The ergogenic benefits are related to increased strength, quicker recovery, decreased infection frequency [209], prevention of overtraining [210], decreased proinflammatory cytokines [211], and intestinal permeability [212], along with increased anti-inflammatory cytokine levels [207,213].

    • The effect of glutamine supplementation on athletic performance, body composition, and immune function: A systematic review and a meta-analysis of clinical trials

      2019, Clinical Nutrition
      Citation Excerpt :

      In these ways, GLN can play a protective role in the stabilization of the intestinal wall [55]. Nevertheless, most of the studies failed to demonstrate any significant effect of GLN intake on the values of CD4+ and CD8+ [14,42,43,48], NK cells activity [14,43,84], B cell counts [14], s-IgA [1,47,84], plasma levels of Ig A, M and G [50,52,54], leukocyte numbers [14,16,41,43,45,48–50], lymphocyte counts [14,16,41–45,48,49], neutrophil numbers [16,42,43,45,48,49], monocyte numbers [43,48,49], plasma concentration of complements [14,50,52], CRP [14], neopterine [14], IL-6 [14], IFɣ [14], ConA stimulated proliferative response [43], LAK [42–44], PHA proliferative response [42,43], and phagocyte activity [50,52]. Based on these findings, it is more likely that GLN does not affect immunosuppression, as has been remarked by athletes.

    View all citing articles on Scopus
    View full text