By Elena Voropay

From so many sports drinks currently on the market, you may become confused about which ones are best to drink during training. How much and how often should you drink? Will the drink make you feel bloated with all the sugar and salt in it? Isn't it better to drink water? Instead of following all the marketing and hype, get to know the well-researched facts about sports drinks and choose them wisely. Remember that only a well-balanced combination of carbohydrates and electrolytes will give you meaningful benefits while you exercise.

Fluid and electrolyte replacement drinks (FER) are excellent for endurance training. These not only help balance the level of hydration by replacing water, but provide essential carbohydrates, minerals and electrolytes many minerals and electrolytes (such as Sodium, Potassium, Calcium, Magnesium, Chloride, Bicarbonate, Phosphate and Sulphate) which get depleted very fast when you are active. The elevated heart rate and muscle work speed up your metabolism and all cells in the body use a lot more fluid and nutrients. Through sweat and breathing your water loss goes through the roof and proper timely hydration becomes paramount.

Why should athletes be concerned about replacing electrolytes during training?

Electrolytes hold on to fluid in the blood and muscles and regulate osmotic pressure between body compartments. They are called this way because they carry electrical currents regulating secretion of hormones and neurotransmitters, work as minerals and enzyme co-factors maintaining a proper acid-alkaline balance of body fluids. Exercise may disrupt this PH (acid-base) equilibrium interrupting all cellular activities within your muscles and nerves, such as coordination, concentration, digestion, muscle contraction and breathing.

During intense training the demand for proper replenishment of these essential micro-nutrients reaches its peak and if you give your cells just what they need at that time you might be able to push through your training plateaus and get the most out of your favourite biking, running or swimming activity.

Different sports drinks contain different kinds of carbohydrates. Which ones are best?

Sports drinks serve a variety of purposes and are targeted for different activities. A good mix and the right proportion of carbohydrates maximize their assimilation and oxidation which is terrific for sustaining your hard training.

If you are looking for something to quench your thirst and get some immediate energy during exercise, then FER drinks will give you just that. Besides electrolytes, they have about 4-8 percent carbohydrates form sucrose, glucose, fructose, corn syrup, maltodextrins and glucose polymers. Glucose, sucrose and fructose are your best energy sources which are easily absorbed by your digestive system and won't cause any gastrointestinal distress during training. Due to their fast assimilation, FERs will keep you blood sugar and liver glycogen levels up during endurance training preventing premature fatigue. Additionally, these have shown to lower the Immediate and Delayed Onset Muscle Soreness usually experienced after an intense exercise session and may speed up recuperation.

Many athletes complain of indigestion and bloating after drinking sports drinks. Is it possible to avoid it?

How well the drink is absorbed reflects on the performance and there are several factors for you to consider. The amount of carbohydrates in sports drinks is the primary determinant whether it will cause digestive distress or not – FER drinks with more than 8 percent (80 grams per litre) of carbohydrates are not recommended during exercise and are better consumed after training for recovery. The reason is that these have lower rate of gastric emptying. Too much carbohydrates consumed at once overwhelms the intestine’s ability to absorb them putting too much pressure on your digestive system. At the same time, muscles are working hard and they need energy, but they cannot oxidize and burn a lot of carbs. As a result, both your physical performance and digestion are compromised. If you drink recommended volumes frequently and allow for slow assimilation of sugars, then you can avoid any unpleasant stomach upsets.

Sodas and fruit juices have over 12 percent sugar concentration, are low in sodium and produce flatulence. Tea, coffee and other caffeinated drinks excrete more water and are natural diuretics, so it's best to avoid them during training. Also consider that cooler beverages are emptied from the stomach faster than hot drinks.

Isn't water better than sports drinks during exercise?

Water may be the most natural inexpensive and easily available choice for hydration. It is demanded by every cell in the body 24/7. However, water does not supply electrolytes and minerals to the extent of sports drinks.

You need to drink 120-180 ml or 4-6 ounces of water every 15-20 minutes of exercise. If you are exercising for several hours, it will add up a lot of fluid making you feel bloated. Additionally, water is excreted faster and may flush out some more electrolytes from your system causing your cells to become even more dehydrated. Drinking plain water may suppress thirst, but it will also stop you from drinking even before you are adequately hydrated.

Sports and FER drinks, on the other hand, have salts and sugars, particularly Sodium, which stimulate your thirst centre in the brain. They also help retain fluid in the tissues and increase blood volume. This translates into a lower heart rate, improved circulation, decreased kidney work and superior performance.

During your training, you loose more than water – you use up all the nutrients, such as carbohydrates and minerals, essential for energy production. No wonder you become tired sooner if water is the only thing you gratify your heart, lungs, muscles and brain for their hard work. With just eight grams of sugars per 100ml, FER drinks help the body absorb the fluid up to 30 percent faster than water. This is the best thing you can do if you've been pushing hard and need to rehydrate in a hurry. Watch the amount of Sodium the drink contains – too much or too little will cause imbalances. The recommended beneficial amount for endurance sports is approximately 70mg per cup(18 mmol/L) hydration.

Creating Your Own Sports Drink

In the days before sports drinks, some athletes made their own sports drinks by mixing defizzed soda. Today many different companies offer FER drinks with better formulations. But since you know more about proper hydration, you can make your own inexpensive sports drink following these simple recipes.

Each cup provides around 6 percent or 14g carbohydrates,100 mg Sodium, 30 mg Potassium and 60 calories :

Mix one cup fruit squash, four cups water and a pinch salt

Blend 1/3 cup sugar with 1L water and ¼ teaspoon salt

Combine ¼ cup orange juice, 4 teaspoon sugar, ¼ teaspoon salt

References

Terrados, N., et al., 1995, Exercise in the heat: strategies to minimize the adverse affects on performance. Journal of Sports Science, Summer, vol. 13 p. 555-62.

Bohl, & Valpe., 2002, Magnesium and Exercise. Critical Reviews in food Science and Nutrition, vol. 42, no. 6, p. 533-63.

Coyle, E., 2004, Fluid and fuel intake during exercise. Journal of Sports Science, Jan, vol. 22, no. 1, p. 39-55. Souped-up Fizzy Drinks. Choice magazine August 2001 pp23-27. Sports Dietitians Australia (1998). Consensus Statement on Fluid and Energy Replacement For Exercise and Sports Activities

American College of Sports Medicine. Position stand on exercise and fluid replacement. Med Sci Sports Exerc 1998;28:i-vii.

Murray R, Bartolli W, Stofan J, Horn M, Eddy D. A comparison of the gastric emptying characteristics of selected sports drinks. Int J Sport Nutr 1999;9(3):263-74

Zachwieja JJ, Costill DL, Beard GC, Robergs RA, Pascoe DD, Anderson DE. The effects of a carbonated carbohydrate drink on gastric emptying gastrointestinal distress and exercise performance. Int J Sport Nutr 1992 2;239-50.

IOC List of Prohibited substances.  Ryan M. Sports drinks: Research asks for reevaluation of current recommendations. JADA 1997; 97 (suppl 2):S197-S198.