Dehydration

 

Dehydration occurs when more water is moving out of the body than what is taken in through drinking.

We lose water every day through breathing, sweating, and urinating.  Contrary to what people usually think, drinking water only when you are thirsty is not entirely good advice.  The thirst mechanism activates usually when the body is under-hydrated.  Dehydration occurs when 1% of body weight is lost in water.  The thirst mechanism is activated at 2% dehydration.  This means we are already in a dehydrated state when we feel thirsty.  Drink more often!

When the weather is hot, we tend to sweat more.  Therefore, if you are exercising in hot weather, you need to be even more diligent about drinking enough water.  Remember that exercise dulls the thirst mechanism.  Keep drinking!

Dangers of Competing while Dehydrated

Dehydrated results in immediate reduction of physical and mental performance.  Dehydration reduces the rate of absorption of water from the intestines, making the reversal of dehydration more difficult.  The negative effects of dehydration are greater within warm environments.

Urine that is light in colour,indicates a well hydrated state.

The hydration status of the body is determined by the balance between water intake and water loss.

If a person does not drink enough fluids, his or her kidneys will try to compensate by extracting more water from the urine, which makes the urine more concentrated.

Check your urine.  It should be clear or pale in colour and copious in volume!  If your urine is the colour of lemonade, you are well hydrated, but if it's the colour of apple juice, you are probably dehydrated.  If your urine is the colour of Coca-Cola, go to the hospital immediately!

Urine that is dark in colour indicates a dehydrated state.
The following table outlines the symptoms of dehydration:

Symptoms of Dehydration

 Percentage of
Weight Lost (%)
 Weight Lost
(lbs)
 Effect
 1% 1.5 (0.7 kg)
  Dehydration begins; impaired temperature control and exercise capacity
 2% 3 (1.4 kg)
  Feeling of thirst, loss of appetite
 3% 4.5 (2 kg)
  Increased pulse rate and body temperature
 5% 7.5 (3.4 kg)
  Difficulty concentrating, headache, irritability, sleepiness
 6% 9 (4 kg)
  Increased respiratory rate, lower blood pressure
 9% 13.5 (6.1 kg)
  Heat exhaustion, heat stroke

 
 
At 6% loss, if you experience these symptoms, you may be in a medical emergency, and you should seek medical help.
 

Watch


The following video illustrates eight common signs of dehydration.