As an endurance athlete it's important to consider the impact dehydration can have and to make sure you're getting enough fluids. Let me illustrate...

On one of my weekly 6 mile tempo runs with a group of friends, I began experiencing some slight cramp-like symptoms in my right hamstring. Thinking it would eventually loosen up, I continued to push the pace until it began getting worse. I told one of my running buddies I would need to back off the remainder of the run. I knew exactly what was happening...

Welcome to the land of dehydration!

To be honest, my dehydration that day (and any day) was due to pure carelessness. I drank a little more coffee that day than usual and failed to take in the amount of water my body needed. Though some studies have found coffee & soda to be nearly equal to water in terms of keeping the body hydrated, the diuretic effect puts more strain on our bowels & bladders. My body just doesn't feel the same or perform at the same level on those high coffee/low water days. In the end, water is just cleaner and what our bodies crave the most.

Why is Hydration So Important?

Water makes up about 60% of our body weight. When we run, we naturally lose water which leads to stiffening muscles, tendons, ligaments and joints. A running cramp is one of the ways our bodies let us know we're suffering from dehydration. I found this out the hard way at the 18 mile mark of the 2008 Akron Marathon. Both hamstrings began cramping and forced me to stop for ten minutes. A police officer noticed the difficulty I was having and actually offered me a bottle of water from his squad car! I gladly accepted. Unfortunately, it's almost impossible to reverse the effects of dehydration in a training run or race. This is why we need to stay hydrated throughout the day rather than trying to cram it all in at the last moment.

Here are some important benefits of water and body function:

• Regulates body temperature
• Moistens tissues for mouth, eyes and nose
• Lubricates joints (like oil in a car engine)
• Protects organs and tissues
• Helps prevent constipation
• Reduces the burden on kidneys & liver by flushing waste products
• Helps dissolve minerals & other nutrients to make available for the body
• Carries nutrients & oxygen to cells

A few Signs of Mild Dehydration:

• Lack of saliva
• Decreased output of urine
• Deep color and strong odor in urine
• Thirst - simply being thirsty is a sign we haven't been drinking enough

How Much Water Do I Need?

We runners and other endurance athletes will naturally need more water than those who aren't as active. On a day off, I use the following formula for my water consumption:

Body weight divided by 2, then change this number to ounces. For example, my body weight is 154 lbs. Dividing this by 2 = 77 lbs. Therefore, I need at least 77oz of water each day. This number increases when we run or exercise in order to replace what we lose in sweat.

When the weather is warmer, our bodies will require even more water due to evaporation. Depending on body weight, each person will vary in sweat loss rate. To find out your personal sweat loss rate, weigh yourself in the nude before going out on a timed training run, swim or ride. Weigh yourself again in the nude upon your return. One pound of weight loss = one pint of water loss. For example, if you lose 2 lbs. of weight in a one hour run, you've lost 2 pints (32oz) of water. This same person would lose 16oz of water on a 30 minute run.

**Note: Studies have found that as little as 2% dehydration can have a negative effect on a race performance.

If I'm going out for a one hour run, I like to drink at least 20oz or more of water 30-45 minutes before my run. This allows enough time for the water to empty the stomach and get where it needs to throughout the body. None of us like that "sloshy" water feeling in the stomach. Drinking too much or eating too close to a run can also lead to those pesky side stitches that seem to take forever to go away.

When I first began running, I carried a water bottle on any run over 30 minutes. After experimenting with my water needs since then, I've realized I don't need to take in fluid during runs that are under 90 minutes, unless it's a very warm day. On a long run day (over 90 minutes), I either carry a water bottle or run a route where I have access to a drinking fountain. A rule of thumb is to experiment on your training runs so you know how your body will react on race day. You don't want to find yourself dehydrated on your long run and still a long way from home. No fun.

Is it Possible to Over-Hydrate? 

Absolutely. Over-hydrating can lead to hyponatremia, a dangerous condition caused by drinking too much fluid. Quite simply, hyponatremia happens when the sodium level in the body becomes diluted (literally flooding the body). In the most serious cases, brain swelling that could lead to seizures and other life-threatening complications can occur. Talk about being watered down! This is one reason it's a good idea to take in some form of electrolyte sports drink on those long runs. By doing so, you replace some of the sodium lost. If I'm going to hydrate with a sports drink, I prefer Nuun tablets

(www.nuunlife.com) since they're made with healthier ingredients. Nuun is not a fuel source with calories. It’s pure hydration and won’t tax the digestive tract.

Dial in the proper hydration for your body and your performance will take off!