I am sure you have always been told how important water is and that you should drink more. However, there is a lot of information available and sometimes confusing, so I am going to simplify it for you.
Facts First:
60% of our body is made up of water (more for children)
85% of our brain is water
95% of social or semi - professional athletes are dehydrated before exercise
80% of your water needs are consumed through drinks; the other 20% is through food
Effects of Dehydration:
Reduced athletic performance (as little as 2% of body weight in water lost can reduce performance by 25%)
Decline in cognition (concentration, alertness, short term memory)
Delirium in the elderly
Gut function (constipation, slowed digestion)
Kidney function (failure - inability to flush out toxins)
Heart (reduced blood pressure, increased heart rate)
Dizziness / fainting (particularly from sitting to standing)
Headache
Reduced ability to heat/cool the body
Hunger
How much to have:
This is the magic question that has been researched for many decades. The recommendation from he Government is to have 2L (8x 250mL glasses) each day. This is the best they can do with the information from research however it does not work for everyone as there are too many variables:
Climate
Activity level
Sweat production
Body surface area
Gender
Ethnicity
Foods consumed
Pharmaceutical drugs
Chronic Diseases
For these reasons the amount of fluid intake will change between different people and will even be different for the same person on a different day. To help with the confusion and uncertainty a far more effective way make sure you receive enough fluids is to monitor yourself especially if you are exercising.
While Exercising:
Again this is very personal and often difficult with the restraints of sport to have regular drinks.
Aim for:
250mL prior to starting exercise
500mL over the course of an hour
500mL after the game/session
NB: small amounts spread over the game is much better than a large amount only at half time.
Signs to show your hydration status include:
1. Urine colour - it should be a pale yellow colour. If it is clear you can cut back on the fluids for a while. If it is any darker than straw - have something to drink. Little and often is more efficient and manageable.
2. Thirst: If you have a dry mouth or are craving a drink, you are already dehydrated so have some fluid.
How to reach appropriate hydration:
1. Water - start simple: have it accessible eg drink bottle so you can have little and often over the course of the day. To make it more enjoyable have it chilled or add some flavouring by soaking strawberries, ginger or lemon in the bottle overnight. This adds flavour without the calories of soft drink.
2. Foods - your food contribute approx 20% of your daily fluid intake. Swapping dry and salty foods like crackers for fruits and vegetables will increase your overall daily intake of water.
3. Beverages - Coffee, tea, soft drink and alcohol all count towards maintaining an appropriate hydration status but they should not be your major source of water. They are often full of calories that lead to issues associated with weight gain and can contain diuretics, meaning; more water will be excreted compared to drinking pure water.
4. Snacks - when you feel hungry it is likely you are also dehydrated. Have a glass of water first before filling up on snacks. This will reduce the feelings of hunger and reduce your urge to snack; keep you hydrated and calories under control.
Life is too short to be held back by dehydration