PROLYTE: We believe that the % solution is the best way to compare drinks. Osmality means little to the average athlete, myself included, and stating this would offer nothing. Compare this to bodybuilding when whey proteins list their "fractions." It may make the product look more impressive, but ask the average bodybuilder what benefits they offer, and you'll probably get a blank look. Same with stating intake of macro-nutrients in terms of grams/kilogram bodyweight. I have no idea how many Kg I weigh, and prefer to know how much I should eat as a percentage of bodyweight in lbs. (you can find this info on our website). Simply put, most people know that a 6% to 10% solution is ideal for quick absorption.

ULTIMA: Ultima Replenisher was designed not only to deliver fluid to muscle cells but also to deliver all of the nutrients necessary for optimum performance and then recovery. This formula was developed with the cooperation of world class elite athletes as well as recreational athletes to demonstrate that the Ultima Replenisher formula would properly support these functions. Using a low osmolarity and hypotonic formula, Ultima Replenisher is rapidly emptied from the stomach and absorbed in the small intestine. Tests have shown that this happens in 15 to 18 minutes. Water is absorbed faster than any other substance, typically at 12 minutes. Since the solution features such a low osmolarity, it is highly absorbable driving the nutrients across the intestinal wall into the bloodstream. This low osmolarity allows the fluid and these nutrients to reach the muscle cells quickly.

When muscle cells are adequately hydrated they do not break down and release protein enzymes, the evidence of muscle cell degeneration. Sports drinks with higher osmolarity values, that is those with hypertonic formulas, do not permit for the same level of absorption in the small intestine. Just because the milligram content number is higher in one formula compared to another, does not mean that your body is absorbing all or even a fraction of what was consumed. Since the entire absorption takes place in the small intestine, the osmolarity and hyper or hypo formulation will determine the real value of the product. Ultima Replenisher was designed to be almost 100% absorbable in the small intestines. This formula design gives the Ultima Replenisher athlete an advantage. Compared to all other sports drinks, Ultima Replenisher provides the most rapid hydration and delivery of nutrients.

ELOAD: Describing the ratio of solute to solvent (grams/100 ml or percent solution) is only a start when characterizing a sports drink. Osmotic pressure (osmolarity or osmolality) is a more useful number. Why? Because this property of solutions ultimately determines the physical characteristics of the solution, and how this solution will interact with human physiology. The lower the osmotic pressure of a solution, the less irritating it is to the human gut. Bear in mind that equal percent solutions of different substances will have different osmotic pressures-this is why percent solution has only limited use.

For example, 1 gram of NaCl (sodium chloride or table salt) in 100 cc of water is a 1% solution. This same solution has an osmotic pressure of 340 mOsm/Liter. By comparison, 1 gram of KCl (potassium chloride) is also a 1% solution. However, this solution has an osmotic pressure of 270 mOsm/Liter, less than the table salt solution. Theoretically, even though they are the same percent solutions, the KCl solution will be less irritating to the gut, if it was ingested, due to its lower osmolality.

e load™ has published its’ osmolarity, along with all other physical information, on its website: www.eload.net.

ECAPS: We feel that osmolality is of extreme importance when discussing fuel strategies. This is because far too often athletes complain of stomach problems which we feel can be directly related to the type of carbohydrate used in a fuel mix. If the osmolality of the solution the athlete drinks deviates from body fluid levels of 280-303 mOsm it will be delayed from absorption until gastric organs can either add more fluid or the electrolytes necessary to create osmolality within body fluid or blood serum level. Because a drink mixture containing simple sugar does not match the same osmolality of regular body fluid, unless it is limited to approximately a 5 percent concentration, it will remain in the stomach until sufficiently diluted. This may cause stomach distress that is obviously detrimental to performance and is why discussion of osmotic pressure is very important. We need to remember that there is a limited amount of calories a 5 percent solution will provide. Usually it is no more than 100 calories, far too little on an hourly basis to sustain energy levels.

GATORADE: The science in this area is very clear: carbohydrate concentration is more important than osmolality, but the combination of the two is critical. The osmolality of a drink refers to the number of solid particles present in a volume of liquid solution. Tonicity refers to an osmolality comparison of one fluid to another. For example, a hypertonic fluid is one that has a higher osmolality than that of body fluid (e.g. blood). An isotonic fluid would have an osmolality that is equal to body fluid. Some sports drinks fall in the isotonic range. Gatorade is the leading example. Other sports drinks are markedly hypertonic (e.g., Powerade). Fluid absorption from the small intestine is dependent on the types and the amounts of carbohydrates and electrolytes in an ingested solution. A majority of carbohydrates and electrolytes in Gatorade are actively transported across intestinal cell membranes. This creates a concentration (osmotic) gradient that promotes a rate of fluid absorption that is as fast or faster than the most hyptonic beverage, water1,2. Beverages that contain too much carbohydrate and too few electrolytes are absorbed more slowly. Case in point: Gatorade is absorbed significantly faster than Powerade and AllSport3.

1. Shi X et al. Med. Sci. Sports Exerc. 27:1607-1645, 1995.
2. Shi X et al. J. Appl. Physiol. 77:1178-1184, 1994.
3. Ryan AJ, et al. J. Appl. Physiol. 84(5):1581-1588, 1998

GPUSH: The composition of fluid formulations used by athletes is significant to their intended use. Certainly, solute concentration is important - fluids having a carbohydrate content less than 8% w/v have been shown to have preferred characteristics for fast gastric emptying and rapid absorption, which ensures rapid rehydration and significant delivery of energy (Vist & Maughan, 1995).

However, It is too simplistic to base usage on simple % concentration of constituents alone. Knowledge of the full osmotic potential of all the ingredients is also necessary. Osmotic pressure is a colligative property of solution and depends on the number of particles in solution. The % concentration does not define the number of particles and so is no guide to osmotic potential. The product range introduced by G-Push Sport is defined in terms of both osmolality and % concentration.

The osmotic potential of our body’s own fluids is approx 290mosm/kg water and is regulated by the intrinsic mechanisms within our own system. Fluids supplied with osmolality above this, i.e. hypertonic solutions, cause not only delays in gastric emptying but 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 which are isotonic, having the same osmotic potential as our own body fluids, are without this effect but those which are marginally hypotonic, that is are below the osmotic potential of the body, are known to be emptied quickly from the stomach and have the potential to be absorbed the most rapidly. (Leiper, 1998).

We have carefully used this information to design our products for optimum combinations of fluid and energy absorption. Our G1 Hydration formula is uniquely designed with an osmolality of 240 molm/kg. Our G2 Momentum formula is formulated to achieve a marginally hypotonic (almost isotonic) solution of 280 mosm/kg. These two formulas are designed to achieve rapid gastric emptying and fast fluid absorption. Both G3 Endurance and G4 Recovery are hypertonic solutions designed to provide energy when glycogen stores are low.

• G1 Hydration – Hypotonic
• G2 Momentum – marginally Hypotonic (almost isotonic)
• G3 Endurance – Hypertonic
• G4 Recovery – Hypertonic