Severe or life-threatening hyponatremia can occur during exercise and is largely associated with endurance activities such as: marathons, triathlons, and ultradistance races.
Symptoms of hyponatremia are:
- impaired exercise performance
- headache, nausea and vomiting
- seizure (convulsions)
- bloated stomach or swelling of hands, legs and feet
- severe fatigue
- confusion and disorientation
- athletes who drink too much before and during prolonged exercise in warm, humid climates
- athletes who sweat a lot or excrete a salty sweat
- those who are overzealous in their drinking habits
References from the SIRC Collection:
1. Beltrami F, Hew-Butler T, Noakes T. Drinking policies and exercise-associated hyponatraemia: is anyone still promoting overdrinking?. British Journal Of Sports Medicine. October 2008;42(10):496-501.
2. Burfoot A. Drink to your health: sure, you should drink regularly. But exactly how much water do you need? And why are some runners dying from excessive fluid consumption. Runner's World. July 2003;38(7):52-54;56;58-59.
3. Manasso J. Too much water can be bad, too. ASCA Newsletter. August 2005;2005(8):6.
4. Murray B, Stofan J, Eichner E. Hyponatremia in athletes: "water intoxication" and subsequent death has become a "hot" topic. How dangerous is it?. Marathon & Beyond. January 2004;8(1):77-82;84-86;92.
5. Nolte H, Noakes T, van Vuuren B. Protection of total body water content and absence of hyperthermia despite 2% body mass loss ('voluntary dehydration') in soldiers drinking ad libitum during prolonged exercise in cool environmental conditions. British Journal Of Sports Medicine. November 2011;45(14):1106-1112.
6. Redmon G. Hyponatremia: Water Intoxication. American Fitness. November 2005;23(6):58-61.
7. Shirreffs S, Maughan R. Urine osmolality and conductivity as indices of hydration status in athletes in the heat. / Osmolalite et conductibilite de l ' urine en tant qu ' indices de l ' etat d ' hydratation des athletes sous la chaleur. Medicine & Science In Sports & Exercise. November 1998;30(11):1598-1602.