75% of your body weight is water.  It’s a fundamental part of each of us, and for the runner, it’s especially important.  We’re constantly losing water in everyday life, but if you sweat during your runs you’re losing water even more quickly.  Dehydration can cause headaches, nausea, muscle cramps, light headedness, dry mouth, and a series of other debilitating issues so use this guide to hydration to make sure that you’re getting enough water and preparing yourself for a successful run every time you put your shoes on.

Your Overall Drinking Routine

Because everybody has a different body type and runs under different conditions, it’s important to pay attention to factors like distance, workout intensity, sweat rate and the temperature where you’re working out so that you can get into a healthy hydration routine.  While you can probably figure out the basics like if it’s hot drink more, you might not have heard of Sweat Rate.
Finding your sweat rate is important because not only is it unique to you, but it will also help you figure out exactly how much water you should be drinking on any given day.

Determining You Sweat Rate

Finding your sweat rate will give you a gauge on how much water you need to drink (or if you need to drink water at all) throughout your run.  To determine your sweat rate, weigh yourself without clothes on prior to and after your run.  As a general rule, your overall weight loss should be no more than 1%.  If it’s more than 1%, you’re not drinking enough water.
You should also remember that for every one pound of weight you’ve lost on your run, you’ve lost one pint (or 16 ounces) of water.  Applying this principle, you should drink 16 ounces of water for every pound you’ve lost on your run.

Before Your Run

Believe it or not, if you’re thirsty then you’re already dehydrated.  Chapped lips are also one of the first signs of dehydration, so don’t wait for these signs to tell you that you need to be drinking water.  Instead, take a proactive approach that starts long before your feet hit the pavement.
They say that if you’re planning on going on a run that’s between eight and ten miles you should start hydrating two days in advance.  This is a good rule of thumb, and you should also be conscious of drinking more in the summer or if you sweat a lot.
On the day of your run, drink 8-16 ounces of water one to two hours before your run.  This gives you the water you need for your workout, but also the time you need to let the water settle a bit.

On Your Run

When you are running…

To Carry or Not To Carry

If you’re going on a run that’s less than 30 minutes to an hour your body should have enough water stored to sustain itself without water.  If you’re planning on going on a more lengthy run though, you should drink between four and six ounces of water every 20 minutes. Rather than drink these amounts all at ounce, take a few sips of water every few minutes to keep you going.

If you need water on your run you can bring a few dollars and buy a bottle at a convenience store somewhere along the way or buy something a bit more durable.  If you’re looking for a long term solution, consider water bottles with handles, CamelBaks, a hydration belt, or other options.

Water Temperature

While the temperature of the water you drink doesn’t matter too much, some studies have shown that cold water actually absorbs faster and helps cool your body temperature slightly.  This keeps you going longer when you need it the most.

When To Use a Sports Drink

Sports drinks with carbohydrates and electrolytes aren’t necessary for runners who go on shorter runs, but if you’re working out for more than four hours, consider adding some sort of supplement to your water to keep you going without cramps or excessive exhaustion.

After Your Run

Hydrating after your run is just as important as hydration at any other point in the day.  While the numbers vary according to your sweat rate, the weather, etc you should consume between 8 and 24 ounces of water after each run.  This will replace what you’ve lost, and send you on your way to positive hydration habits that will manifest themselves in your next run.
Also, make sure to consume some protein and carbohydrates to replace what you’ve burned on your run.  If you want to learn more about what you should be eating as a runner, see our Optimum Runner’s Diet Guide.