The key to good hydration is drinking a lot of water before, during and after any workout or activity. Water is essential for proper bodily function. According to a recent study, after 2% of a person’s body weight is lost through perspiration, the person experiences impaired performance. After 4%, the capacity for muscular work declines, after 5% heat exhaustion, 7% hallucination, and after 10% you experience circulatory collapse and heat stroke. Water however contains no electolytes or carbohydrates.
Sports drinks do not hydrate better than water. Water though does not taste nice so we tend to stop drinking before we are fully hydrated. Sports drinks contain sugar or a sugar substitute and flavour, meaning it has a better taste. This means we drink more leading to better hydration.
Juice is not to be advised for hydration, as it is not absorbed by the cells very quickly.
So if you are training for less than one hour try putting down the sports drink and top up on the water.
You really don't like water and have decided to opt for the sports drink, in addition you keep reading about replacing electrolytes, so what gives?
What are electrolytes?
Electrolytes serve three general functions in the body
• many are essntial minerals
• they control osmosis of water between body compartments
• they help maintain the acid-base balance required for normal cellular activities
The electrolyte composition of sweat is variable but comprises of the following components:
•Sodium
•Potassium
•Calcium
•Magnesium
•Chloride
•Bicarbonate
•Phosphate
•Sulphate
There are three popular types of sport drinks available.
Isotonic
Hypotonic
Hypertonic
Isotonic
Isotonic is the most polular sports drink and replaces fluids lost by sweating and a boost of carbohydrates. This would be favoured the those training for middle to long distance running, gym work or us martial artists.
Glucose is the body's preferred source of energy therefore it may be appropriate to consume Isotonic drinks where the carbohydrate source is glucose in a concentration of 6% to 8%.
Hypotonic
This would be prefered by those needing fluid replacement, but without the need for a carbohydrate boost. Gymnasts for example.
Hypertonic
To be used to supplement daily carbohydrate intake normally after exercise to top up muscle glycogen stores. In ultra distance events, high levels of energy are required and Hypertonic drinks can be taken during exercise to meet the energy demands. If used during exercise Hypertonic drinks need to be used in conjunction with Isotonic drinks to replace fluids.
Can I make my own?
This BBC website has details on making your own Isotonic, hypotonic and hypertonic drinks.
A simple isotonic drink can be made with 200ml of orange squash (concentrated orange), 1 litre of water and a pinch of salt (1g). Mix all the ingredients together and keep chilled.
I have had some success with water, the juice from a few limes (adjust to taste) and a couple of unrefined salt crystals.
So do they work?
Jeanette Crosland, the consultant sports dietitian to Paralympics GB had this to say: -
Sports drinks are good for intensive sport, but if you're doing half an hour of badminton, water will be fine. But they're definitely not designed for kids to take in their lunchboxes.”
The energy-packed drinks are an essential piece of kit for running a 10km race, or for taking part in a triathlon or a sports match, especially in hot weather, as they contain sodium, which helps to prevent dehydration by replacing the amounts you lose when you sweat. Sodium is essential because drinking large amounts of plain, unsalted water over a long period of exertion (four to six hours) can dilute blood plasma and make you feel ill. However, their high- energy content makes them very calorific, and will not help if you're trying to lose weight.
They're not designed for someone who is overweight and going to the gym for half an hour, as one litre contains 240 to 300 calories. They could end up drinking more than they are expending.
http://www.atg.wa.gov/teenconsumer/health_and_safety/sports_drinks.htm
http://www.brianmac.co.uk/drinks.htm
http://chemistry.about.com/cs/foodchemistry/a/aa070803a.htm
