Sweat Stuff

Very recently I attended a Hydration workshop that was organized for a group of ladies. The turn out was great and that meant I wasn't alone in my quest to learn more about this topic.

I was expecting to dispel a few theories and confirm some other ideas I had about hydration. .

Questions on my mind ranged from how do I hydrate before a ride, how do I manage my fluids during the ride and after my ride? Do I only drink when I'm thirsty? Or do I drink before thirst sets in?

Sometimes I do a good job in the hydration department and sometimes I end up with dizziness and headaches after a ride even though I felt I was well hydrated. Obviously something is amiss.

I set out to this workshop searching for clarity. To figure out where I was going wrong and how to avoid those post ride headaches and the dizziness and wobbly feelings immediately after my ride.

I'm hoping to clarify things for myself and in turn I hope it helps someone else out there too.

We hear a lot of things in the media and many times it's some sort of product endorsement, this creates a lot of unnecessary confusion and can detract from diagnosing what you actually need to be mindful of in your own situation.

I did some sound research and below is what I surmised.

The Basics

What is Hydration About?

Hydration is about maintaining our total body water. We are about 55-70% total water depending on our lean mass. Lean muscle holds more water.

We have 3 major compartments in our bodies.

Intracellular space inside our cells

Extracellular space outside our cells

Vascular space (in the blood vessels) and Interstitial space (between the cells).

Our bodies are remarkable machines, capable of maintaining a system of self regulation (homeostasis).

Homeostasis keeps the body functioning within a normal range by maintaining a stable a environment.

Our bodies are constantly working to maintain our blood pressure at all times. The body controls this by a series of mechanisms such as thirst, sweat , breathing and eliminating waste.

Water shifts between compartments based on changing electrolytes (mostly sodium and potassium).

It's the water and electrolyte balance that determines how most of our systems function especially our nerves and muscles.

 

Let's look at some factors that affect hydration.

1. The Environment: Temperature, Humidity, and Altitude

In Dubai, we are subjected to excessive heat for many months out of the year.

2. Exercise intensity and duration=energy expenditure (calories)=heat load

3. The Individual Person: fitness levels, surface area, weight.

All of these contribute to HEAT LOAD.

How does our body cope with all that heat load?

  1. The blood vessels in our skin vasodilate , blood flow to the skin increases in order to remove heat and there is a redistribution of blood flow in our system. This leads to something called

  2. Relative Hypovalemia: There is no fluid loss at this stage,but because of this redistribution of blood flow, the blood in the vascular system(blood vessels) decreases this results in a drop in blood pressure putting a load on the cardiac system. The cardiac system responds by increasing our heart rate.

  3. Sweating: We lose water and electrolytes as our bodies try to cool down via the evaporation of sweat.

Heat load creates competition between trying to dissipate heat and supplying vital oxygen to our muscles.

It takes as little as a 2% decrease in body water to lead to dehydration and performance detriments in sports. It doesn't matter how you became dehydrated, heat or no heat. If the water loss is there your performance will suffer.

Let's have a look at the symptoms of

Dehydration:

Faintness an inability to stand or walk ( that's me with the dizziness and wobbly feelings)

Muscle cramps as the water to muscles is diminished

Rapid breathing;

Weak rapid pulse

Cognitive impairments as the brain shrinks in severe dehydration

Loss of consciousness

How can I determine my hydration status?

The best way to determine hydration status is by taking your weight before and after exercise to determine the total body water loss . The difference in weight is the water loss that needs to be replaced.

How should I replace fluid lost?

When we sweat we lose water and electrolytes.

90% of that is sodium chloride and it's this one that is absolutely critical to replace.

5% potassium

3% calcium

2% magnesium

If someone were to only drink water during a long intense exercise session this would not sufficiently replace sodium lost.

For a one hour exercise session you most likely do not need a sports drink and something like coconut water or plain water will be sufficient.

For long events, sodium concentration and fluid replacement really matters.

Let's talk about Pre-Hydration

Pre-Hydrating is an important concept. This can help fill the void caused by the relative hypovolemia we spoke about earlier. Where the blood vessels in the skin were dilating to dissipate heat through the skin.

It is better to pre-hydrate with electrolytes 15 minutes before exposure to heat.

It is recommended to drink 1 liter of sodium citrate(720-3500mg per liter) and 2-3% sugar solution.

And to answer my own question of thirst, here is what I took away. It is better to stay ahead of your thirst. “Don't chase your thirst, stay ahead of it.”

So hydrating during exercise is important. Sip your water during exercise as needed.

As we become dehydrated it becomes difficult to maintain our core temperature. When our core temperature gets too high we tend to start to shut down no matter what. Blood pressure drops, cardiac output suffers, heart rate increases.

To help keep your core temperature down, keep your drinks cold, the colder the better

Find a protocol that works for you, you are unique. practice your own hydration strategy. Something that works for one individual may not necessarily work for another.

And on a side note..

One of the best ways to check if you are over-hydrating is to take your weight before and after exercise, if you are heavier than you started then you drank too much.

A few symptoms of over-hydrating

Weight gain

Nausea and vomiting

Muscle weakness and fatigue

Feeling of apprehension

High blood pressure

Rapid pulse

As for me, I will be paying more attention pre-hydration with electrolytes before I set out on a ride. 

If you continue to suffer from dehydration symptoms despite all your efforts, it is probably best to get a sweat test. Dehydration is dangerous and can really ruin any experience.

I hope this helps. Feel free to leave your comments.