After a long day in the classroom, the bell finally sounds for the end of the day. You jump out of your seat and rush off to the locker room to change for your afternoon’s sports session. You barely have enough time to tie your shoes before running down to the field.

Your mind is already on the field or in the pool. You don’t even think about having something to drink. Five minutes into training, your mouth starts to feel dry, you start feeling lethargic and a bit dizzy. And you are gasping for something to drink. There’s a good chance you are dehydrated.

More than two thirds of the human body is water. We cannot make water or store it. The only way for the body to get the water it requires is for you to drink water and other caffeine-free, sugar-free beverages throughout the day1.

 

The Functions Of Water In The Human Body

We would not survive without water. It is involved in almost every structure and function in the human body. The functions of water include2:

  • The regulation the body temperature
  • The elimination of waste products through urine, faeces and perspiration
  • Prevention of constipation
  • Aids in digestion
  • The absorption of nutrients
  • Transporting nutrients around the body
  • Supports brain function
  • Involved in all biochemical processes

When you don’t drink enough, things start to go wrong. Bodily processes don’t run as smoothly as they should and we begin to show signs of dehydration.

 

The Effects Of Dehydration

Your body is constantly losing water. Every time you go to the toilet or take a breath, water is leaving your body. On a hot day or when you are exercising, you lose even more water through perspiration.

The amount of water in your body is controlled through various finely tuned mechanisms3. As soon as your body senses that your water levels are running a bit low, the thirst sensation is triggered. You are driven to go and find something to drink. When you ignore your thirst, you run the risk of becoming dehydrated.

The early signs of dehydration involve thirst, darker urine and going to the toilet less often. As you continue to lose water without replacing it your mouth might start to feel dry. You may start to feel lethargic and weak. Headaches and dizziness are also common when your brain is not getting enough water4.

 

How Does Dehydration Affect Sports Performance?

On the sports field, dehydration can have a negative impact on your performance – both physical and mental. Your heart rate and your body temperature rise and it starts to feel like the exercise is very strenuous. These effects are especially bad when you are exercising in the heat5.

If left uncorrected, dehydration can cause diarrhoea, vomiting, nausea and other issues with the gastrointestinal system during exercise. The more dehydrated you are, the more difficult it becomes to correct your body’s fluid balance. The absorption of water from the intestines is reduced, which can make you feel bloated and sick6.

8 Tips For Staying Hydrated

The importance of replacing lost water cannot be denied. To maintain your fluid balance and to ensure that your body functions optimally, you constantly need to replace the water you lose throughout the day. Use these eight tips to stay on top of your hydration:

  1. Drink when you feel thirsty
  2. Aim for the recommended six to eight glasses of water per day
  3. Drink more when you exercise
  4. Increase your water intake when the weather is hot
  5. Make sure to include the electrolytes sodium and potassium if you sweat a lot during exercise
  6. Eat fluid-filled food – fruit and vegetables
  7. Drink something else if you don’t like water – water is always the first prize, but tea, coffee, juice and carbonated water are also useful for staying hydrated.
  8. Start your day with a glass of water

It is not only your exercise performance that is affected. School work and other activities are made easier when your body is well hydrated. Drinking enough water everyday can make it easier to stay alert in class and prevent fatigue when you hit the sports field in the afternoon. Aim for a minimum of six to eight glasses of fluid per day, but remember to add more if it is a very hot day or you are exercising.

 

References

1. Jéquier E, Constant F. Water as an essential nutrient: the physiological basis of hydration. European Journal of Clinical Nutrition [Internet]. 2009 Sep 2 [cited 2021 Dec 1];(2):115–23. Available from: http://dx.doi.org/10.1038/ejcn.2009.111
2. Benelam B, Wyness L. Hydration and health: a review. Nutrition Bulletin [Internet]. 2010 Mar [cited 2021 Dec 1];(1):3–25. Available from: http://dx.doi.org/10.1111/j.1467-3010.2009.01795.x
3. Riebl SK, Davy BM. The Hydration Equation. ACSM’S Health & Fitness Journal [Internet]. 2013 Nov [cited 2021 Dec 1];(6):21–8. Available from: http://dx.doi.org/10.1249/FIT.0b013e3182a9570f
4. Shaheen NA, Alqahtani AA, Assiri H, Alkhodair R, Hussein MA. Public knowledge of dehydration and fluid intake practices: variation by participants’ characteristics. BMC Public Health [Internet]. 2018 Dec [cited 2021 Dec 1];(1). Available from: http://dx.doi.org/10.1186/s12889-018-6252-5
5. Carlton A, Orr RM. The effects of fluid loss on physical performance: A critical review. Journal of Sport and Health Science [Internet]. 2015 Dec [cited 2021 Dec 1];(4):357–63. Available from: http://dx.doi.org/10.1016/j.jshs.2014.09.004
6. El-Sharkawy AM, Sahota O, Lobo DN. Acute and chronic effects of hydration status on health. Nutrition Reviews [Internet]. 2015 Aug 19 [cited 2021 Dec 1];(suppl 2):97–109. Available from: http://dx.doi.org/10.1093/nutrit/nuv038