The Importance of Osmolality

Introduction to Osmolality

Osmolality is a term used to describe the concentration of particles dissolved in a solution. It is a measure of density and is expressed in units of measurement known as osmoles or milliosmoles (one thousandth of an osmole), per 1000g of solvent, or mosm/kg. The more particles a rehydration beverage contains (such as carbohydrate, electrolytes, amino acids, anti-oxidants, protein or flavoring), the higher its osmolality.

Optimal absorption of fluids within the body happens when a sports drink solution is equal in terms of osmolality to what naturally occurs in the body. The osmolality of our body’s own fluids are approx 300mosm/kg water and are regulated by the intrinsic mechanisms within our own system.

• Fluids supplied with osmolality above 300mosm/kg, (i.e. hypertonic solutions), cause not only delays in gastric emptying but also more importantly will cause fluid shifts from the body to the gut before absorption occurs. Such delays in rehydration introduce the real potential to delay and reduce performance. (Alonso, 1998, Hargreaves, 1991, Sowka et al, 2000).
• Solutions that are isotonic, (having the same osmolality as our own body fluids), are without this effect.
• Solutions, which are marginally hypotonic, (that is are below the osmolality of the body), are known to be emptied quickly from the stomach and have the potential to be absorbed the most rapidly. (Leiper, 1998).

As the osmolality of your sports drink increases above 300 mosmol/kg, efficient uptake from the GI tract is decreased. In fact, solutions with high osmolalities (hypertonic) can actually draw fluid out of the body. For the everyday person, this is not a problem. However, for athletes who are turning over large volumes of fluids and electrolytes, it could literally mean life or death. (Or, perhaps at the least, finishing instead of a DNF).

Osmofit is a Patent Pending Process that automatically calculates the osmolality of your personal race drink guaranteeing that is will easily digest and give you the results you are looking for.