When our core body temperature rises (due to physical exertion or illness) we excrete sweat onto the surface of our skin. Our body heat is transferred to the fluid on the skin and it evaporates removing the heat form the body and cooling us.
The fluid we sweat not only removes water from our bodies, but also electrolytes which must be replaced to maintain homeostasis within the body.
Sweat rates and sweat electrolyte concentration a highly variable between individuals and can be effected by;
Work demands – Activity intensity, duration
Environment (temperature, relative humidity etc.)
Individual differences – age, body composition, fitness level
Level of heat acclimatization
Dietary electrolyte intake levels
*Average electrolyte content of sweat has been estimated at;
Sodium: 900mg/L
Potassium: 200mg/L
In a study in the JOURNAL OF OCCUPATIONAL MEDICINE AND TOXICOLOGY in 2008, the average sodium loss over an 8-12 hour work day was 4800-6000mg of sodium. With sweat losses from 10-12L. Hyponatremia occurs when there is low sodium concentration in the blood.
This can occur due to the practice of overhydrating, where by people drink too much water due to excessive thirst during long duration activities often in the heat without replacing the lost electrolytes. An ideal fluid replacement beverage for industrial use should have significant sodium content with minimal carbohydrate.
Sports drinks deliver an excessive amount of sugar and required fluid volume is high if trying to replace electrolyte losses. Most likely the amounts of sports drink required to replace electrolytes simply would not be tolerated due to flavor fatigue and GI discomfort.
Oral Rehydration Solutions such as SOS Hydration are highly concentrated electrolyte formulations designed to replace what is lost in incidents of high electrolyte loss. Any sugar contained is at low levels and is for palatability and assistance.
The team at SOS are dedicated to working with clients to ensure the most appropriate and effective use of their product, for more information please contact SOS Hydration Sports Science Director and technical advisor Andy Garlick, [email protected] or (03) 9028 2677