BRITISH YOUTH WOMEN SQUAD
Hydration for Athletes
Although carbohydrates are essential for providing energy, your body also needs water to function optimally. With an average of 65% of your body consisting of water, it plays a crucial role in many processes in the body. Allof us should aim to drink at least 2 litres of fluid a day to keep our bodies fully hydrated. For regular sports participants, fluid intake becomes even more important. During exercise, body temperature increases and we start to sweat. For this reason, water intake needs to be increased to replace the additional fluids lost as sweat.
Fluid loss by sport
In general, it’s quite easy to lose at least one litre of fluid during each training hour. So, you could easily lose 2% of your body weight through sweat during exercise. The exact volume of sweat lost will vary depending on the type, duration and intensity of exercise but average levels are indicated in the graph below. Remember, losing as little as 2% of your body weight as sweat can impair performance.
Combating fluid loss
Here are some simple steps you can follow to limit the chance of becoming dehydrated and avoid the detrimental effects dehydration can have on performance. • Aim to drink a minimum of 2 litres of fluid every day as part of your regular diet routine.

• Make sure you drink additional fluids before, during and after exercise. As a general rule, aim to drink 200-500m1 of fluid 2 hours before exercise. This will ensure that you start exercise well-hydrated but have allowed enough time for any excess to pass as urine.
• In addition, you should aim to drink 125—150 ml of fluid every 15—20 minutes during exercise to top up lost fluid levels.
• Replace any fluid that you have lost during training in your recovery period. The presence of electrolytes, such as sodium in the fluid you drink post-exercise will aid hydration further by improving fluid retention.
• Begin replacing fluid immediately after exercise by drinking at least 500 ml of liquid. To gain complete rehydration, the volume of fluid consumed should be equivalent to 150% of the body weight lost during exercise i.e. for every 1 kg body weight lost, aim to drink at least 1 .5 litres of fluid.
Rehydration
If you do not replace the fluid lost through sweating, your body will become dehydrated. In response to this dehydration, you will feel thirsty and your body will try to conserve the fluid that it has left, so it will reduce the amount of sweat and urine. The effects of dehydration are cumulative and can eventually lead to heat stroke and, in extreme circumstances can be fatal.
Thirst is not a good indicator of dehydration. By the time you feel thirsty your body is likely to already be dehydrated and your performance will already have begun to suffer. Monitoring the amount of urine you excrete and its colour can help to provide you with an indication of your hydration status. Generally, the darker in colour your urine and the less you urinate, the more dehydrated you are. Ideally, your urine should be a pale straw colour. However, please be aware that other factors can also affect urine production and colour. Urine colour is only intended as general guide to hydration status.

Use this pee chart’ as a guide to your level of hydration and need for fluid.

 Q&A
When should I start drinking to ensure I am fully hydrated before exercising?
It is generally recommended that you drink at least 2 litres of water every day. even when you are not exercising. A regular intake of fluids throughout the day is better than trying to drink a large volume in one go as more of it will be retained by the body. You should aim to drink 400—600 ml of fluid about 2—3 hours before you begin to exercise. This will ensure that you start exercise well hydrated but have allowed enough time for any excess to pass as urine.
Is it possible to drink too much fluid?
There have been occasional reports of ultra-endurance athletes drinking too much fluid and developing hyponatraemia (low sodium levels in the blood) but these cases are rare. Usually, any excess fluid that is consumed is simply excreted in urine. For most athletes, the risk of becoming dehydrated during exercise is far greater than the risk of consuming too much fluid so don’t let concerns about over consumption prevent you from drinking plenty of fluids before, during and after exercise. However if you are worried about drinking to much fluid, avoiding plain water and drinking something that contains sodium, such as an isotonic sports drink, can help prevent blood sodium levels falling too low.