BY: Angela Leach   /   DATE: April 2018

Roughly 60% of the human body is made up of water, which is a good indication of its importance for all bodily functions and this certainly does not exclude sporting performance. Did you know that just 1% dehydration can lead to a reduction in strength?  Learn the ins and outs of good hydration by reading on.


Many people fail to see the value of good hydration in their sports, until they have experienced the dehydration. Common symptoms of dehydration include fatigue, muscle cramps, dizziness, headaches, mouth dryness and loss of coordination, which can severely impair performance with effects such as:

  • A reduction in physical and mental performance
  • Increase in heart rate and body temperature,
  • increased perception of how difficult the exercise feels
  • Impaired skill level
  • Increase the risk gastro-intestinal problems during and after exercise.



Day to day we need to make sure that we are meeting our fluid requirements. As a guide it is often recommended that we drink 6-8 glasses or 1.5-2l of water per day, but often relying on thirst is the best indicator because individual requirements vary. It is a good idea to fill a water bottle(s) in the mornings and keep it on your desk to drink during the course of the day. Although water should be our primary source of fluid, we can also fulfil some of our requirements with other drinks and foods. Fruit, veg, dairy products such as yoghurt and soups are all good food sources of fluid. Drinks to use with caution include:

  • Sugar sweetened beverages- these contain empty calories, providing little or no nutrition. Certain cold drinks may also have a diuretic effect, worsening dehydration.
  • Alcohol- alcohol in moderation (1-2 servings per day) is alright, however be aware that besides being harmful to the body, alcohol can have a negative effect on your sporting performance, nutritional status and cause dehydration in excess.

Around exercise

No two people are the same, likewise people vary in how easily they dehydrate. Get to understand your hydration levels better by weighing yourself before and after training. The difference in weight will be the result of fluid losses. In order to compensate for these losses, drink 1l-1.5l per kg lost.

BEFORE: Make sure you always start an exercise session session well hydrated, but beware of overhydrating before as this can lead to increased urination and GI upset during exercise

DURING: In events lasting less than 60-90 minutes you can use thirst as indicator, however longer sessions usually require planned fluid intake. Requirements usually vary between 150ml to 350ml of fluid at 15-20 minute intervals. Beverages with carbohydrate concentrations of 4% – 8% can be handy for intense exercise events lasting longer than 1 hour because they provide for both part of the athletes fluid requirements as well as carbohydrate replenishment requirements. Sports drinks are ideal in this situation as they provide the correct carbohydrate concentration, fluids and electrolytes which assist with rehydration and prevent hyponatremia.

  • AFTER: You do not stop losing fluids as soon as you stop exercising. You continue to dehydrate through sweat and urine losses after you finish exercising. Aim to replace 125-150% of all fluid lost in the hours following exercise. To rehydrate effectively drink your fluids along with salty recovery snacks which will provide much needed electrolytes.


Making sure that you are properly hydrated can be instrumental in maximising your sports performance. Following the guidelines above and learning exactly how your body’s fluid regulation works is definitely worth your effort if you want to be the best athlete you can be.