Staying hydrated is essential for everyone, but athletes have an even greater need to maintain proper hydration. Water is the most important nutrient for life and has many important functions including regulating temperature, lubricating joints and transporting nutrients and waste throughout the body.

 
Keeping hydrated for exercise
Knowing what to drink and how much when you’re exercising can be difficult and varies from person to person. Here we offer some advice on hydration
Whether you’re an elite athlete or a weekend warrior, it’s important to keep hydrated when you exercise.
We’ve got some top tips to guide you on how much you need to drink, and what, before, during and after exercise.
 
Why is it important to stay hydrated?
Around 60 per cent of your body is water and it plays a vital role in every bodily function. You can lose a lot of fluid when you exercise – up to a litre an hour – mainly through sweating and breathing. 
If you don’t top these fluids back up, you can get dehydrated. Being dehydrated can affect both your general health and how well you can exercise. You’ll feel tired more quickly and won’t be able to control your temperature as well as usual.
Water helps fuel your muscles, so drinking before, during and after exercise will boost your energy levels, and may help to prevent cramp.

 
BEFORE EXERCISE
It may not cross your mind but making sure you’re well hydrated before you exercise is really important, especially in hot conditions. 
If you’re dehydrated before you even start exercising:

• your core temperature will rise faster

• your heart will have to work harder than usual 

This will affect your performance and can even lead to heat stroke. Drinking enough will help you get the most out of your exercise session and feel good while you’re doing it.
One quick way to test if you’re hydrated is to check the colour of your urine.

 

 

DURING EXERCISE
Being dehydrated can affect your energy levels. Your muscle cells are almost three-quarters water so if you're short on fluids, you’ll feel the strain. Drinking little and often rather than a lot less often will give you the best chance of hitting your exercise targets.
The amount you need to drink will depend on how much you sweat and how long you exercise for. How much you sweat is influenced by your: 

• genetics – some people sweat more than others

• size – larger people tend to sweat more than smaller people, and men sweat more than women

• fitness – fitter people sweat more and earlier in exercise because their bodies are accustomed to needing to cool down

• environment – you sweat more in hot, humid conditions

• exercise intensity – you sweat more as you exercise harder

The best way to figure out how much to drink is to respond to what your body tells you. Simply put, if you feel thirsty, drink. Here’s another way to work out how much fluid you lose while exercising and how much to drink to compensate for it.
 
The sweat rate calculation
Weigh yourself before exercise (do this before going to the toilet).
Weigh yourself after exercise.
Compare the figures.
 
For every kilogram of body weight you lose, drink up to a litre and a half of fluid.
 
 
AFTER EXERCISE
​Once all the hard work is over, no doubt you’ll be ready for something to drink. Not only will this be refreshing, but it will also restore your fluid levels and help your muscles to recover. The sooner you start to replace the fluid, the sooner you’ll recover.
 

Top tips
* It can take time for fluids to be absorbed into your body. Drink steadily during the day and aim to drink around 500ml of fluid at least four hours before you exercise. In the 10 to 15 minutes before you exercise, top your fluid levels by drinking about half of this again.
 
* Make sure you always have a bottle of water handy when you exercise so you don’t get dehydrated.
 
* Don’t be tempted to reward yourself after exercise with a pint. Alcohol is a diuretic, which means it removes water from your body by increasing how much urine your kidneys produce.