Caffeine, Body Fluid-Electrolyte Balance, and Exercise Performance

Click name to view affiliation

Lawrence E. Armstrong
Search for other papers by Lawrence E. Armstrong in
Current site
Google Scholar
PubMed
Close
Full access

Recreational enthusiasts and athletes often are advised to abstain from consuming caffeinated beverages (CB). The dual purposes of this review are to (a) critique controlled investigations regarding the effects of caffeine on dehydration and exercise performance, and (b) ascertain whether abstaining from CB is scientifically and physiologically justifiable. The literature indicates that caffeine consumption stimulates a mild diuresis similar to water, but there is no evidence of a fluid-electrolyte imbalance that is detrimental to exercise performance or health. Investigations comparing caffeine (100-680 mg) to water or placebo seldom found a statistical difference in urine volume. In the 10 studies reviewed, consumption of a CB resulted in 0-84% retention of the initial volume ingested, whereas consumption of water resulted in 0-81% retention. Further, tolerance to caffeine reduces the likelihood that a detrimental fluid-electrolyte imbalance will occur. The scientific literature suggests that athletes and recreational enthusiasts will not incur detrimental fluid-electrolyte imbalances if they consume CB in moderation and eat a typical U.S. diet. Sedentary members of the general public should be at less risk than athletes because their fluid losses via sweating are smaller.

L.E. Armstrong is with the Departments of Kinesiology, Nutritional Sciences, and Physiology & Neurobiology at the University of Connecticut. Storrs, CT 06269-1110.

  • Collapse
  • Expand
All Time Past Year Past 30 Days
Abstract Views 1589 1 0
Full Text Views 7087 1271 130
PDF Downloads 4709 1136 112