The Athletes' Guide To Sports Drinks
By Jeff Volek, PhD, RD | Monday, July 16, 2012 12:42:55 PM America/New_York
wave of sports drink offerings
Sales of sports drinks are in the hundreds of billions worldwide. It's no surprise there are a lot of choices and a lot of new companies that want a piece of this growing market. Sports drinks traditionally were designed to replace fluid and electrolyte losses during and after exercise. But now they contain various other concoctions of nutrients and are used for more than just rehydration. Here's a brief rundown of the established brands and a few new products to consider.
Should You Rehydrate?
The way the body controls body water is complex, varies from person to person, and changes on a daily basis. On average your body weight can vary plus or minus 4% from day to day, which is mainly due to changes in body fluid status. Exercise is one factor that drives fluid loss (hypohydration), especially if you are exercising in hot and/or humid conditions due to excess sweating. Fluid loss adversely affects endurance performance, but research also indicates that on average hypohydration decreases strength and power 2-3% and high-intensity endurance performance by approximately 10%. In addition to losing water, sweat contains minerals like sodium and potassium. With prolonged exercise and excessive sweating replacing sodium and potassium becomes increasingly important. Electrolyte losses vary widely from person to person making specific guidelines for replacement highly personalized. The bottom line, it pays to take some precautions against losing significant amounts of body water and electrolytes.
Gatorade and Powerade
Based on the pretty simple idea that athletes should replace the water and electrolytes that are lost during exercise, researchers at the University of Florida developed Gatorade in 1965. The composition has changed slightly over time but after 40 years Gatorade remains the top selling sports drink accounting for well over half of all sports drinks sold. The basic formula for Gatorade has always been water, salt, and sugar with flavoring. In the late 1980s, Powerade was introduced as a major competitor to Gatorade. From an ingredient standpoint, they both contain sugar syrups (about 14 to 19 grams per 8 oz) and salt (50 to 110 mg). There is a lot of attention lately on the downside of excessive sugar consumption, which raises concerns about the use of these sports drinks. Clearly if you are not active, the sugar is not needed. But even if you are an athlete a strong case can be made that consuming high fructose corn syrup and other simple sugars is not the optimal way to deliver fuel. Simple sugars draw water into the gut, and they stimulate insulin which inhibits fat breakdown and fat burning. Thus, some companies have tried to improve upon these long-established sports drinks.
An emerging concept with growing support is the idea of adding protein to carbohydrate to improve performance and recovery. Accelerade is a sports drink and rehydration beverage that includes protein in addition to simple sugars and electrolytes. The ratio of carbs to protein is a constant 4 to 1. Several studies have shown that adding protein to carbohydrates enhances endurance performance by as much as 50%. It is unclear what the exact mechanism is but it may help prevent protein breakdown during exercise, decrease muscle damage, prevent central fatigue, or provide alternative fuel by way of branched chain amino acids. A typical serving of Accelerade has 30 grams of sugar and 7.5 grams protein. This provides a lot more sugar than Gatorade and Powerade, and the protein actually enhances the insulin response further. Again, this may not be ideal if you are an athlete wanting to access fat for fuel during exercise and recovery.
Vitargo is a complex carbohydrate made from waxy starch rich in amylopectin. Compared to glucose, the size of the carbohydrate in Vitargo is massive with a molecular weight between 500,000 to 700,000 g/mol (glucose = 180). The fact that Vitargo is made up of thousands of glucose molecules means that it has a very low osmolality, which simply means solute concentration measured as the number of particles in one liter of water. Drinks with a low osmolality leave the stomach quicker than ones with a high osmolality and thus are generally associated with less gastrointestinal stress. That's why Gatorade and Powerade limit the sugar to amounts that keep their beverages at a 4-8%. Otherwise they would sit in the stomach longer and increase the potential for gastrointestinal distress. Vitargo not only leaves the stomach quickly, it is also rapidly digested and absorbed into the blood stream. Thus, Vitargo spikes blood sugar and insulin levels after ingestion providing a rapid source of carbohydrate fuel which may help speed glycogen synthesis.
A product gaining popularity among active individuals is SuperStarch, a fuel source developed by the UCAN Co. SuperStarch was originally developed for the treatment of a rare childhood genetic disorder that manifested in a need to be fed a source of carbohydrate at frequent intervals to maintain blood glucose levels. SuperStarch was developed as a strategy to better manage the disease by providing extended maintenance of blood glucose. SuperStarch is a complex carbohydrate made from waxy maize rich in amylopectin with a similar high molecular weight to Vitargo. Thus it exerts low osmotic pressure in the gut. Unlike Vitargo, SuperStarch is processed using a proprietary heat-moisture method that actually slows digestion and absorption providing a long-lasting steady source of fuel without surges in blood glucose or insulin. By avoiding large increases in insulin, ingestion of SuperStarch allows for greater access to fat stores for fuel while still providing an extended source of blood sugar. This is particular relevant for individuals who need sustained sources of fuel or those wanting to improve body composition or metabolic health.
PowerCoCo is a new company that has developed a flavored coconut electrolyte beverage. Coconut water naturally contains potassium and smaller amounts of sodium. It's sweetened with small amounts of sugar cane and natural stevia delivering 25 Calories and 5 grams of carb per 8 oz serving. Thus compared to traditional sports drinks like Gatorade and Powerade, PowerCoCo has one-third the sugar. PowerCoCo also contains more potassium than sodium, whereas other sports drinks contain more sodium. For most people, they get plenty of sodium from foods but potassium is lacking. Thus PowerCoCo is a natural and healthier way to rehydrate and provide electrolytes without stimulating a surge in blood sugar and insulin. PowerCoCo actually tastes very good considering it is not loaded up with simple sugars like traditional sports drinks and overall represents one of the most interesting new products this category has seen in years, especially for carb conscious athletes and bodybuilders. Recently a number of high profile professional athletes, including Carmelo Anthony, have switched over to this innovative lower sugar alternative due to the fact that it is more physique friendly than previously established products.
With the blistering summer heat and humidity now upon us, make sure this critical aspect of sports nutrition is not overlooked, especially when training vigorously outdoors.