What is dehydration?
Dehydration is the loss of water and important blood salts (like potassium).
What does dehydration do?
If you are suffering from dehydration vital organs such as the kidneys, brain, and heart can't function as they require a certain minimum of water and salt.
Does the body help us prevent dehydration?
The body tries to stay around a temperature of 37 degrees by sweating.
This results in the loss of body fluid. If fluid levels are reduced it can lead to dehydration and heat stroke.
What are the tell-tale signs of dehydration?
You are probably dehydrated if you are thirsty, have dry lips and a dry mouth. You may also have a headache.
A more serious form of dehydration occurs if you have blue lips, a weak pulse, quick breathing and confusion.
When should I drink on a race day?
You should start drinking early on a race day.
With two hours to go until the match starts, drink up to 600ml of fluid.
Then, with 15 minutes to go drink around 500ml of fluid.
During long races it is important to consume liquid when you can. If possible, aim for 100-150ml every 15 minutes.
Afterwards, try and drink immediately. This will ensure you do not dehydrate.
How can I check that I am drinking enough fluid?
Every time you play sport, you lose a considerable amount of fluid.
The best way of checking that you are drinking enough is to look at the colour of your urine. If you are well-hydrated and drinking the correct amount of water it should be a very pale yellow colour. If your urine is very dark - usually a brownish-green colour - you are dehydrated and have not consumed enough fluid.
A more accurate way of monitoring that you are drinking adequate amounts of fluid is by weighing yourself before and after exercise. For every kilogram lost you have lost a litre of fluid and need to drink 1.5 litres to prevent dehydration.
What should I drink?
Isotonic drinks are the best.
Isotonic drinks contain between 6-8 grams of carbohydrates in every 100ml. They also contain salt which allows the body to use the fluid efficiently.
Almost all types of non-alcoholic drinks prevent dehydration.
Water is the most popular form of fluid because it is cheap and accessible. It also is very effective.
Some drinks such as cola, lemonade and high energy drinks often contain over 10 or more grams per 100ml. These kind of drinks stop the body being able to use the fluid because they take so long to absorb.