If you've done p90x, you know that Tony says "Drink your water people!!"  This email is about the importance of hydration for athletic performance.  In a world that is trying to find the "perfect" pre-workout supplement or magic formula for performance, we often overlook the fact that water is the main component in our blood and maintaining a fluid balance in the body is essential.  Blood delivers oxygen, nutrients, hormones, and a multitude of other substances to cells and removes metabolic by-products from cells.  Did you know that about 66% of a person's total body weight is from water?  Did you also know that well-hydrated muscles are made of about 75% water? 

Two Quick Tips
Perhaps the first most important tip I can give you is that the thirst mechanism doesn't kick in until you are already well on your way to being dehydrated.  Because of this, you must hydrate effectively during the day, during the workout, and after the workout to assure that you are in correct balance.  My second quick tip is to avoid is hyperhydration.  If you "forgot" to hydrate during the day and decide to drink a lot of water all at once, the result is that the concentration of electrolytes, protein, and glucose in your blood will be less than normal.  Why?  Because you just "flooded" your body with water.  This will shut down the production of ADH (antidiuretic hormone), diluted urine will be produced, and you will not be effectively hydrated.

Entering exercise, being in a state of optimal hydration is important.  Even a minor level underhydration (as little 2% of body weight) can cause to a measurable difference in endurance and performance.  One of the body's indicators that you are properly hydrated for exercise is that the urine is clear in color.  If you have been hydrating consistently during the day, and not relying on "thirst" as your guide, you should easily be able to attain this level.  I've read that about 60-90 minutes before exercise is the time to consume a large volume of fluids (up to 1/2 liter).  This will ensure that you are good to go around gametime, and also will aid in what is known as "gastric emptying," which is the rate at which fluids pass from the stomach out into the intestines to be delivered to the muscles.  Finally, you should try to avoid foods and drinks with diuretic properties near performance time.  This includes anything with caffeine and high sodium foods.

During Workout

Consistent fluid intake during a workout will decrease two things: the body's core temperature, and the heart rate needed to delivery the same amount of oxygen to the muscles.  Both of these factors can be summed up with the word: efficiency.  If your heart has to work harder and your sweat mechanism needs to work harder to cool off your body, you will not perform at as high a level.  The question here becomes - should I drink plain water, or should I drink a sports beverage?  Realistically, a sports beverage is actually ideal if you want to perform at the highest level.  Carbohydrates in the fluid help avoid the depletion of muscle glycogen and provide fuel for the muscles when glycogen is low.  There is also evidence that carbohydrates will improve mental function during exercise.  When "choosing" your carb in your sports drink, know that glucose (dextrose), maltodextrins, and simple starches are all about the same positive effect, but fructose and sucrose (which includes a fructose molecule attached to a glucose molecule) may cause some GI stress since fructose isn't digested until it reaches the liver.  So as you read labels on sports drinks, keep this in mind.  You shouldn't have more than about 1g of carbohydrate per minute of intense exercise.

Even if you have been hydrating, it is likely that after the workout you will be slightly underhydrated.  It is ok to therefore take in a large volume (.5 liter or so) of liquid right after the exercise, and then consistently sip water for hours after the workout.  Again, a fluid with a carbohydrate is preferable post-workout, and additionally about 10g of protein included in the drink may quicken glycogen replenishment.  Electrolytes including sodium in the drink are also preferable to help retain the fluid.  It is therefore ok to have a small handful of pretzels or a salty low-fat snack after the workout.  We all love to "weigh in" after a workout because most likely due to fluid loss we will seem lighter than we really are.  Just note that for about 1 pint of retained fluid in the body is equivalent to about a pound of body weight.  So, if you weigh in a pound under when you started, you will need more than 1 pint of water to help replenish this loss.  

"Recovery" Drinks
I've written a full article about post-workout nutrition.  Many recovery drinks contain a 4:1 ratio of simple carbs to protein and include other supplements like l-glutamine and Vitamin C to help curb cortisol levels and promote muscle growth.  For more information on the P90X recovery drink, which in my opinion has an ideal balance of all of these qualities, click here.

Calories in Sport Drinks
One thing to note is that when you take in sports drinks that include simple sugars and some protein, you DO have to "count" the calories as part of your daily consumption.  However, just know that you are utilizing these calories to benefit your athletic performance, hydration, and eventually recovery.  So for the "average" person, do I suggest using a sports drink during AND after exercise?  Maybe not, but it depends on your goals.  In the past months, I have changed my goals to not only continue to get toned and in shape, but to really perform at a higher level DURING my workouts, whether it be Insanity DVD's or running.  Therefore, I am treating my nutrition like an athlete's nutrition, trying to include substantial carbs in daily diet and using recovery drinks and sports drinks during performance.  By doing this, I have definitely burned more calories during the workouts by working harder than ever before, perhaps even enough extra calories to "negate" the calories from the carbs I have been ingesting around the workout.  However, it can be an equally smart solution for some of you who are trying to burn fat to workout hydrated, but without the extra carb boost to possibly burn fat more directly as a source of energy.  When your glycogen levels get to low levels, you will not perform as well during the workout, but you will be burning fat more directly, so it's a trade off.  If you take my approach - performance during the workout over all else, you will probably burn more calories TOTAL, get more benefit from a cardiovascular perspective, and raise your metabolism during the day by having pushed yourself hard in your anaerobic zone.  

Bottom line - is whether you include the carbs or not, staying hydrated is KEY!  So bring that water bottle with you to work and keep it full, sipping all day.  Not only will you perform athletically better, but most likely your mind will be in the game more and you will be less lethargic in every day life.