Water Intoxication: A Possible Complication During Endurance Exercise

  title={Water Intoxication: A Possible Complication During Endurance Exercise},
  author={Timothy David Noakes and Neil John Goodwin and Brian L. Rayner and Trevor Branken and R. K. Taylor},
  booktitle={Medicine \& Science in Sports \& Exercise},
Abstract NOAKES, TIMOTHY D., NEIL GOODWIN, BRIAN L. RAYNER, TREVOR BRANKEN, and ROBERT K.N. TAYLOR. Water intoxication: a possible complication during endurance exercise. Med. Sci. Sports Exerc., Vol. 17. No. 3, pp. 370–375, 1985. Four athletes developed water intoxication (hyponatremia) during endurance events lasting more than 7 hours. The etiology of the condition appears to be voluntary hyperhydration with hypotonic solutions combined with moderate sweat sodium chloride losses. The reason… 

The dipsomania of great distance: water intoxication in an Ironman triathlete

It is confirmed that symptomatic hyponatraemia is caused by considerable fluid overload independent of appreciable NaCl losses and that athletes be warned not to drink excessively large volumes of fluid (dipsomania) during very prolonged exercise.

Exercise-Associated Hyponatremia During Winter Sports

Clear evidence indicates that EAH is a dilutional hyponatremia caused by excessive fluid consumption and the inappropriate release of arginine vasopressin.

The incidence of hyponatremia in prolonged exercise activity.

  • B. Toy
  • Medicine
    Journal of athletic training
  • 1992
To prevent hyponatremia, participants should acclimatize themselves to race conditions prior to the event and endurance athletes should be encouraged to ingest low sodium concentrate drinks during events lasting longer than 4 hours.

Hyponatremia in distance runners: fluid and sodium balance during exercise.

  • T. Noakes
  • Medicine
    Current sports medicine reports
  • 2002
It is established that the potentially fatal condition of symptomatic hyponatremia would be eliminated from sport immediately if all athletes were advised of the dangers of ingesting as much fluid as possible during any exercise that lasts more than 4 hours.

Encephalopathy due to severe hyponatremia in an ultramarathon runner.

A case of severe hyponatremia with life-threatening encephalopathy that developed in an ultramarathon runner after he dropped out of a race because of foot blisters is presented and it is postulate that much of the ingested water was absorbed only after he discontinued exertion.

Recurrent Hyponatremia in the Endurance Athlete: A Case Study

The current body of knowledge in these areas is presented to guide primary care providers in the treatment of athletes with emphasis on fluid restriction, necessary laboratory tests, monitored use of hypertonic intravenous solutions, and recommendations for training and race strategies for endllrance athletes who experience RAE.

Hyponatremia in Distance Athletes

  • T. Noakes
  • Medicine
    The Physician and sportsmedicine
  • 2000
The case report of Flinn and Sherer is so important for it records a potential tragedy that was prevented by expeditious and appropriate medical care that conflicted with popular dogma.

Exercise-associated hyponatremia.

The epidemiology, pathogenesis, and therapy of exercise-associated hyponatremia, a condition associated with sustained physical exertion during marathons, triathlons, and other endurance athletic events, are reviewed.

Exercise-associated hyponatremia.

Recommendations for Treatment of Hyponatraemia at Endurance Events

Care providers should consider the use of intravenous hydration with normal saline carefully since it is not needed by most collapsed athletes and may worsen the condition of patients with unsuspected hyponatraemia, and use of hypertonic saline should be reserved for patients with severe symptoms.



Changes in serum electrolyte levels during marathon running.

  • I. CohenA. Zimmerman
  • Medicine
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde
  • 1978
It is recommended that athletes drink an augmented volume of fluid during marathon running, irrespective of the prevailing weather conditions, because of a highly significant fall in serum magnesium concentration and an increase in both potassium and sodium levels.

Biochemical parameters in athletes before and after having run 160 kilometres.

  • T. NoakesJ. Carter
  • Medicine, Biology
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde
  • 1976
Plasma free fatty acids levels were very markedly raised in 12 of the runners, the highest increases occurring in group A, and the blood glucose levels increased slightly but remained within normal limits in all the athletes at the end of the race.

Physiological and biochemical measurements during a 4-day surf-ski marathon.

Surf-ski paddling is associated with low sweat rates, low levels of dehydration, low body temperature and unchanged renal function, and the low post-exercise blood glucose levels indicate that competitors must eat high-carbohydrate diets for the duration of the event and must either eat carbohydrate-containing foods or drink concentrated carbohydrate solutions while paddling.

Water and electrolyte replacement during repeated days of work in the heat.

It was concluded that the addition of electrolytes to drinking water is of minimal value for subjects who dehydrated (-3%) on repeated days and are permitted to ingest food and drink libitum.

Metabolic responses to a 90 km running race.

The overall metabolic response to marathon and ultramarathon running is not substantially different, and serum insulin levels were reduced, whereas serum potassium and triglyceride levels were unchanged.


  • D. Costill
  • Biology
    Annals of the New York Academy of Sciences
  • 1977
The intent of the following discussion will be to detail the composition of sweat and to describe the alterations in body fluid compartments during prolonged exercise, attention will be given to the changes in water and electrolyte contents of muscles and plasma during exercise of long duration.


The performance of physical work in the heat can be affected for better or worse by a variety of factors, the most important being physical fitness and acclimatization, nutritional state, clothing

Muscle water and electrolyte distribution during prolonged exercise.

Observations confirm earlier findings that exercise and electrolyte losses in sweat and urine do not alter the calculated membrane potential of active and inactive muscle.


  • C. Wyndham
  • Physics
    Annals of the New York Academy of Sciences
  • 1977
The correct precaution would be to prohibit the race in circumstances in which an occurrence might be expected-a moisture laden atmosphere, a following wind and the early afternoon of a day with a shade temperature of 85” F (29.Y C) or higher.

Effects of ultra-marathon training and racing on hematologic parameters and serum ferritin levels in well-trained athletes.

This study shows that serum ferritin levels may be subnormal in a proportion of distance runners and that daily training and ultra-marathon racing in particular may cause these levels to remain elevated for between 6--14 days.