Sports Drink Specifics: What Should You Shop for in a Sports Drink?

When choosing a sports drink, let science guide you to the best formula to fit your sports performance needs. First, eliminate the low-calorie formulas. There isn’t enough scientific evidence to support the use of low-calorie formulas for improved athletic performance. The scientific purpose of a sports drink is to provide fluid volume to prevent dehydration, supply carbohydrate and electrolytes to the body during exercise, and be both tolerable in taste and digestibility.

A sports drink that meets these requirements will typically contain a 6-8% carbohydrate solution or about 14 grams of sugar per eight ounces of fluid. A concentration lower than that may not be concentrated enough to provide sufficient energy to fuel working muscles, and any concentration higher than 8% may not absorb quickly causing malabsorption of the carbohydrate resulting in cramping and bloating. The body is typically able to absorb 60 grams of carbohydrate per hour, and a study by Jeukendrup and colleagues demonstrated an upper tolerance of 72 grams of carbohydrate per hour when different forms of carbohydrate were ingested. Due to this limited rate of carbohydrate absorption, there may be a place for less concentrated sports drinks for endurance athletes that need to consume a large volume of fluid to prevent dehydration over a 4-5 hour period. Also, choosing a sports drink that contains more than one type of carbohydrate is important to aid in absorption. Those athletes competing in events lasting less than 120 minutes who do not require excessive fluid intake would most likely benefit more from a standard formula such as, but not limited to, Gatorade or Powerade.

Along with carbohydrate, electrolytes such as sodium and potassium are vital to maintaining fluid balance and sustaining proper muscle function. Sodium consumption during exercise specifically improves body water retention, increases plasma sodium levels, manages thirst, and stimulates the kidneys to retain water.² Choosing a sports drink that contains around 200 mg per eight fluid ounces is ideal to keep you hydrated during a long workout.³ Any sport drink with sodium levels between 20 and 35 mg per eight fluid ounces can be eliminated from your choices since they will not provide adequate electrolytes for training.

Additional nutrients that may be listed on a sports drink label include protein, B-vitamins and magnesium. The scientific evidence for inclusion of protein during endurance exercise is not yet conclusive, although science has proven protein as an important nutrient for enhanced recovery. The B-vitamins act as coenzymes in energy metabolism, therefore their purported use in sports drinks and energy drinks is to enhance energy levels through more efficient energy metabolism. Research still has not been able to prove their efficacy as an energy enhancer. Finally, magnesium is an electrolyte associated with muscle contraction and has recently been added to some sports drinks to help control cramping in tired muscles. Use caution with magnesium however because it has a low tolerable upper limit. Consuming more than 350 mg within a short time frame can cause nausea and vomiting. When it comes to the best sports drink to improve athletic performance simple may still be better. Always experiment with a new drink during training never in competition, and if you have questions ask a Sports Dietitian to help you select the formula that is best for you.

1. Jeukendrup A, Moseley L, Mainwaring GI, Samuels S, Perry S, Mann CH. Exogenous carbohydrate oxidation during ultraendurance exercise. J Appl Physiol. 2006;100:1134-1141.
2. Stachenfeld, N. SSE #111 Assessing Hydration in the Laboratory and Field. www.gssiweb.org. Retrieved August 16, 2013, from http://www.gssiweb.org/Article/sse-111-assessing-hydration-in-the-laboratory-and-field
3. Haudum J. Commercially Available Sports Drinks: What to Look for, When to Consume. SCAN’s Pulse, 2013,32:1-5.