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Sports drinks also have other functional ingredients added. A basic sports drink will have water, carbohydrates and electrolytes. Some of the more target specific sports drinks may also have protein, vitamins and minerals, caffeine or amino acids. You may want some of these additional ingredients, depending on what the sports drink is for. Electrolytes act as buffers in the blood stream to ensure cells maintain proper function and help with water movement and retention in the body. Most sports drinks add sodium and potassium for this. According to the Institute of Sports Medicine, sodium plays a very important role in helping to retain water to prevent dehydration, so sodium is important. The effect of potassium as hydration aid in sports drinks has been found to be minimal. Added calcium and potassium would be good examples of minerals that are important to muscle function. They may help people prone to muscle cramps during exercise. Zinc has been shown to help the body use energy more efficiently. Magnesium can promote relaxation after a workout. Studies have shown protein and carbohydrates consumed within an hour after exercise increases muscle synthesis and decreases fatigue. Milk, whey and soy protein have all been shown to be very effective post workout. This helps to decrease damage to the muscles and reduce fatigue. Amino acids at amounts as low as 1% have been shown to have an effect on performance and fatigue. This would be an ideal addition to a sports drink that would be consumed during endurance exercise, such as a marathon or triathlon.

Summary:
Have an understanding of all of the ingredients. Check for electrolytes. Choose a drink with vitamins and minerals. Choose a drink with added protein for a post workout recovery drink. Choose a drink with added amino acids.