Depression of plasma glutamine concentration after exercise stress and its possible influence on the immune system

Med J Aust. 1995 Jan 2;162(1):15-8. doi: 10.5694/j.1326-5377.1995.tb138403.x.


Objective: To determine whether plasma glutamine levels can be used as an indicator of exercise-induced stress, and to consider the possible effects of low plasma glutamine concentrations on the immune system.

Methods: We used two exercise regimens: in Trial 1 seven male subjects were randomly stressed on a treadmill at 0, 30%, 60%, 90% and 120% of their maximal oxygen uptake (VO2max); in Trial 2 five highly trained male subjects underwent intensive interval training sessions twice daily for ten days, followed by a six-day recovery period.

Results: Plasma glutamine concentrations decreased significantly from an average of 1244 +/- 121 mumol/L to 702 +/- 101 mumol/L after acute exercise at 90% VO2max (P < 0.05) and to 560 +/- 79 mumol/L at 120% VO2max (P < 0.001). Four of the five subjects showed reduced plasma glutamine concentrations by Day 6 of the overload training trial, with all subjects displaying significantly lower glutamine levels by Day 11. However, glutamine levels showed a variable rate of recovery over the six-day recovery period, with two subjects' levels remaining low by Day 16.

Conclusions: Reduced plasma glutamine concentrations may provide a good indication of severe exercise stress.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Exercise / physiology*
  • Exercise Test
  • Exercise Tolerance / physiology
  • Glutamine / blood*
  • Humans
  • Male
  • Muscle, Skeletal / metabolism
  • Physical Education and Training
  • Physical Endurance
  • Stress, Physiological / blood*
  • Stress, Physiological / immunology*
  • Time Factors


  • Glutamine