If you relish a quick outdoor workout, even in the summer, or are a regular gym-goer, you simply can’t escape the scorching temperatures and humidity. And all the summer sweating leaves you thirsty and dehydrated. You might even be addicted to sweet and sugar-laden sports drinks without realising it. It's okay as long as you put in a power-packed workout - you reason with yourself. But do you think that sports drinks are healthy for you? Which is better for the average person exercising - a sports drink or good old water? We asked Senior Dietitian, Sunita Roy Chowdhary of Rockland Hospital, New Delhi and here's what she has to say about whether water is better than sports drinks or not:

“Water is the most popular drink during exercise, but sports drinks do a better job of hydration”. How true is this statement?
It is right to say that sports drinks do a better job of hydration than water. Dehydration during exercise is caused due to sweating in which water and body’s electrolytes are lost.  During exercise sweating occurs so as to maintain the core temperature of the body. Carbohydrate stores of the body are also depleted during exercise as the muscles use the glycogen stored in them as well as that of the liver.

Sports drinks are made up of water, salt, electrolytes, glucose or glucose polymers and fructose. Glucose and salt increase the absorbability or uptake of water in the body. The absorption of plain water as compared to the sports drinks is less and therefore, sports drinks improve hydration.

There are two main factors which affect the uptake of a drink or fluid in the body

• The speed at which it is emptied from the stomach
• The rate at which it is absorbed through the walls of the small intestine.

Glucose in the drink will prevent blood glucose levels to fall too low and also help to maintain body’s glycogen stores. Sodium and potassium are the main electrolytes which help maintain the hydration and reduce urine output.

What drink is the best for getting and keeping hydrated during exercise? 

1. Water: Water causes bloating which will suppress thirst and therefore drinking; water contains no carbohydrate or electrolytes and it also increases urine output.
2. Sports drinks: These enhance performance during exercise, have a good absorbability as they are isotonic (meaning that they have a similar composition to that of body fluids). Isotonic fluids, because of their good absorbability quickly replace fluids lost by sweating and supply a boost of carbohydrates.
3. Juice: Juices are hypertonic, that means they have more carbohydrate or glucose molecules per ml.  They may be nutritious but are not a good choice for hydration. The fructose or the fruit sugar in the juices reduces the rate of water absorption so the cells do not get hydrated quickly. Hypertonic fluids should be taken along with Isotonic solutions or in diluted form. They should normally be taken after exercise.
4. Carbonated beverages: Carbonated beverages cause dehydration. They have caffeine and thus have a diuretic effect which means that they increase urine output. Also they have a bloating effect and give a feeling of fullness. This inhibits the natural thirst mechanism.

Are there different recommendations for sports drinks and water for regular gym goers, body builders and athletes?
Yes, there are different recommendations for the regular gym goers, body builders and athletes. It is difficult to generalize the amount and the type of fluids to take as it all depends on the length and intensity of the exercise. It also depends on the height, weight and body type of the person. Outdoor exercisers need more fluids and electrolytes as compared to people exercising in an AC environment. 

Consuming sports drinks is beneficial for maintaining hydration, electrolyte and glucose levels. This improves performance and replenishes the glycogen stores. Water can be taken on a regular basis for flushing the system and approximately about 3 to 3.5 liters of fluids per day must be consumed.

• Isotonic sports drinks immediately replace fluids and electrolytes lost by sweating and supply a boost of carbohydrate. These drinks work well for longer exercise sessions, replenishing fluids, electrolytes and carbohydrates. Examples of natural isotonic drinks are coconut water, sweet salted lemon water.

• Hypotonic sports drinks replace only fluids and electrolyte lost by sweating, and has minimal or no carbohydrate content in it. These drinks are best used for rapid hydration and are not optimum for exclusive use during long sessions of exercise. Examples of natural hypotonic drinks are salted lemon water

• Hypertonic sports drinks have high carbohydrate content to top up muscle glycogen stores during or after the heavy exercise sessions. These are better post-exercise drinks that offer a higher dose of energy with the fluid. If used during exercise it is recommended to use it with isotonic drinks. Examples of natural hypertonic drinks are packaged juices.

Your final verdict - sports drink or water?
During exercise or sports activities a lot of sweating takes place to maintain the body’s core temperature. This leads to loss of body’s fluid and electrolytes and if not controlled can lead to dehydration. Also the body’s carbohydrate stores are depleted during exercise. Plain water can replenish the fluid lost during exercise but not the electrolytes and the carbohydrates. It also gives a feeling of fullness and increases urine output. Sports drinks do not hydrate better than water, but provide carbohydrates and electrolytes which are lost during the exercise session. They can be consumed in larger quantities as compared to water because of their sweet taste. 

It is advisable to take sports drinks (natural or packaged) immediately before, during and after the exercise session or the sports events, if you are involved in high intensity training. But otherwise water is a better source of hydration taken on a regular basis for the average gym-goer. 

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