Hydration: How Much is Enough?

Those of you who have had the “pleasure” of participating in a group class that I have coached know that it irks me when one of our CrossFitters stops in the middle of a short workout like “Fran” or “Helen” to get a drink of water. I always politely inform the offending (and oftentimes unsuspecting) CrossFitter that they will not get dehydrated in a 10 minute workout!

If your workouts last 30 minutes or less you should be able to just hydrate before and after your workout and be okay. Only if your training sessions are over 30 minutes in duration should you also be drinking water during your training session.
Signs and Symptoms of Dehydration

• Mild to excessive thirst
• Fatigue
• Headach
• Dry mouth
• Little or no urination
• Muscle weakness
• Dizziness
• Lightheadedness

Low levels of dehydration do have physiological consequences. A loss of 2% bodyweight (just 3lbs for a 150lb person) causes an increase in perceived effort and is claimed to reduce performance by 10-20%. A fluid loss exceeding 3-5% bodyweight reduces aerobic exercise performance noticeably and impairs reaction time, judgment, concentration and decision making – vital elements in all sports, from pole-vaulting to football. A particular issue for boxers is that dehydration increases risk of brain injury.

Protecting against Dehydration

One of the most important things to remember about proper hydration is that, not all hydration is created equal. For example; one cup of coffee is not equal to one cup of water. That’s because coffee is a diuretic (causes you to excrete fluid via urine) – so are many other beverages, such as tea and soda.

How Much Water Should You Drink?

There are a million viewpoints on how much water is enough. Some examples include the 8 glasses of 8 ounces per day rule or the one ounce for every pound of weight rule (Wow that is a lot of water!). But the problem is that none of these takes into account factors such as altitude, climate, exercise, nutrition intake, etc. that can all affect the amount of water lost each day.

My Method of Staying Hydrated

I actually learned this from a member of our armed services when I was over in Iraq in 2004. It is very simple and precise.

First of all, you need to remember that 1 gallon of water weighs 8 pounds. Then, identify your bodyweight when your hydration level is optimal. How can you tell when it is optimal? When you are urinating consistently every 2-3 hours with clear urine, you are well-hydrated. This should be consistent over several days before you give yourself the hydration “stamp of approval.”

If you are hydrated and weigh in at 150 pounds prior to your workout and after the workout you weigh in at 146 pounds, you have lost 4 pounds of water or 1/2 gallon. You will then need to simply drink 1/2 gallon, slowly, and you will return to your optimal hydration level.

You have to be careful not to trick yourself into thinking you are hydrated by downing a lot of water at once. Your cells can absorb water only so fast, and the more dehydrated you are, the slower this absorption rate is. This is a protective mechanism to keep you from drowning your cells with too much water.

If you drink excessive water or you drink the right amount of water too quickly, it will build up in the intercellular spaces and end up back in the bloodstream and filtered out of your body by the kidneys. This will make you urinate more frequently, maybe every 15 minutes, until the excess water is out of your system. You might inadvertently think you are hydrated at this time because the excessive water you are excreting will dilute the contaminants in your urine that make it normally look like nuclear waste.
Here are 5 Random Hydration Tips to Get You Started:

1. Drink often, Drink slowly – Slow and steady helps your cells absorb the water and reduces waste.
2. Avoid distilled water (unless minerals were added) because distilled water has no minerals and will leech the minerals from your body.
3. Know your hydration weight, and weigh in before and after your workouts to determine how much water you need to drink to stay hydrated.
4. Water is best – Avoid Energy drinks (like Gatorade) unless working out in the extreme heat or for periods greater than 30 minutes.
5. Don’t drink too much water, too fast. An upset in your electrolyte balance can lead to hyponatremia and death.