Water is essential to maintain blood volume, regulate body temperature and allow muscle contractions to take place. In sports people, this is very importance and an element that can dramatically affect their performance


When we exercise and heat up, the way that our body maintains body temperature and cools us down is by sweating. The sweat (in the form of water and salts) comes to the top of the skin and evaporates to cool us down. Therefore, sweat results in fluid loss.

For the cells in our body to work well, it is important that their water content is maintained at the correct level. This means our body must maintain a balance between the water we take in and the water we lose. This is done by the kidneys. The kidneys keep the balance of water in our body in check, and they also control the levels of salts in the blood, and the excretion of metabolic waste.


Drinking fluid d

uring exercise is necessary to replace fluids lost in sweat. Remaining hydrated throughout exercise will reduce the risk of heat stress, maintain normal muscle function, and prevent performance decreases due to dehydration. It is also important to be hydrated to be able to allow the kidneys to let enough water go to be able to flush the build-up of metabolic waste (that quite often cause DOMS, lethargy etc) from exercise.



Dehydration occurs when the loss of body fluid, exceeds the amount that is put in, resulting in the body not having enough fluid to be able to carry out its normal functions efficiently.

As dehydration increases there is a gradual decrease in physical and mental performance. Your heart rate increases, your body temp increases and your rate of perceived of how hard the exercise increases. In extreme cases, loss of co-ordination, impaired decision making and an increased risk of heat stroke can occur.

Thirst is not a sign of hydration status. Once your thirsty, there has generally been a significant fluid loss.


  • You should aim to match your sweat rate with fluid intake. To measure your sweat rate, take your weight before exercise, then after the exercise session dry off as much water as possible, and weigh yourself again. The difference should indicate relatively how much fluid was lost in that training session.
  • Always start exercise well hydrated.
  • Sip water during exercise. Too much water can cause gastric disruption and may make you feel sick or bloated and uncomfortable.
  • Continue to drink water after you finish exercise.




Is water.

However, if you are competing in an endurance sport or high intensity sport, a carbohydrate and electrolyte drink can help with hydration levels during the event for added energy and so the sodium lost after
excessive sweat, the salts can help the body then uptake the fluid.