As a follow-up to last week's blog: how do you know when you are properly hydrated?  

A good sign that you are properly hydrated is the colour of your urine (yes, I went there). Normal urine colour ranges from pale yellow to deep amber — the result of a pigment called urochrome and how diluted or concentrated the urine is. 

Pigments and other compounds in certain foods and medications can change your urine colour. Beets, berries and fava beans are among the foods most likely to affect the colour. Many over-the-counter and prescription medications give urine vivid tones, such as red, yellow or greenish blue.1 

What happens when you are dehydrated? 

1. The viscosity of your blood goes up, causing your heart rate to go up.  
2. You deplete the electrolytes, including sodium, chloride, and small amounts of potassium, calcium, magnesium, iron, copper and zinc in body, possibly causing muscle cramps.  
3. Body temperature goes up marginally, blood is used as ‘radiator fluid’.  

At about 1%-2% dehydration, the body starts to tell the brain we are thirsty, so please take on fluids. If you don’t heed the warning signs and levels increase to 2%-4% dehydration, then the nervous system senses that your body is in danger, and it starts to go into a false-safe mode and starts to protect the body, by slowing you down. Higher than 4%, the body slows right down, if you are running, it may even cause you to walk or worse. 

Can you overhydrate? 

Hyponatremia2. What? Hypo what? Hypo-Na-tremia is when you literally ‘poison’ your body by drinking too much water and the sodium levels become dangerously low. Most cases have occurred after prolonged activity in hot and humid conditions, where the participant only consumed water. In rare cases, some athletes and army recruits have died of this condition. The worse thing is the condition presents itself like being dehydrated, you feel like you need to drink and you maybe lethargic and having headaches. 

Bottom line dehydrated or suffering from hyponatremia, the initial treatment is similar: fluids with electrolytes, not plain water, especially if your event is longer than 60 minutes. 

Next week we will talk about how to deal with the heat. 

1- https://www.mayoclinic.org/diseases-conditions/urine-color/symptoms-causes/syc-20367333 

2- https://www.gssiweb.org/en/sports-science-exchange/article/sse-88-hyponatremia-in-athletes