Vitamin C supplementation does not alter the immune response to 2.5 hours of running

Int J Sport Nutr. 1997 Sep;7(3):173-84. doi: 10.1123/ijsn.7.3.173.


This randomized, double-blind, placebo-controlled study was designed to determine the influence of vitamin C supplementation on the immune response to 2.5 hr of high-intensity running. Twelve experienced marathon runners (VO2 max 51.6 +/- 1.5, age 40.5 +/- 2.0 years) were randomized into vitamin C (1,000 mg/day for 8 days) or placebo groups. On the test day, subjects ran at 75-80% VO2 max for 2.5 hr, with five blood samples taken before and for 6 hr after. Blood samples were analyzed for cortisol and catecholamines; leukocyte subsets; interleukin-6; natural killer cell activity; lymphocyte proliferation as induced by concanavalin A, phytohemagglutinin, and pokeweed mitogen; and granulocyte phagocytosis and activated oxidative burst. Compared with placebo, vitamin C supplementation had no significant effect on the pattern of change in any of these hormonal or immune measures following 2.5 hr of intensive running.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Ascorbic Acid / immunology*
  • Ascorbic Acid / pharmacology
  • Double-Blind Method
  • Epinephrine / blood
  • Female
  • Humans
  • Hydrocortisone / blood
  • Immune System / drug effects*
  • Interleukin-6 / blood
  • Killer Cells, Natural / drug effects
  • Lymphocyte Subsets / drug effects
  • Male
  • Middle Aged
  • Running / physiology*


  • Interleukin-6
  • Ascorbic Acid
  • Hydrocortisone
  • Epinephrine