How To Determine Your Fluid Needs

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How much fluid do you really need? How To Determine Your Fluid Needs

Several different factors all go into constructing and implementing a successful training program for runners. Of course, there’s the obvious stuff like nutrition and workout design that most people immediately think of when they set out to layout their training.

But then there are other aspects that tend to go unnoticed. Things like rest, recovery and even your environment should also be considered. And each of these factors can have major impacts on your training – for good or bad. Counted among these oft-neglected but vitally important considerations is that of hydration. Sure, athletes think a lot about their fluid needs when they’re… you know, thirsty but what about the rest of the time. What should you know about your hydration habits and needs?

Fluids vs. Water

You might have noted the use of the word “fluid” rather than “water.” This is not simply to sound scientific. No, there’s an important distinction to make here that has a heavy influence over how you hydrate before, during and after exercise.

While water is generally the go-to beverage for athletes and health-minded individuals, it’s not your only option. To be sure, water is highly important. Not only does the liquid help to maintain a healthy core temperature but it’s also a major component in your blood and numerous tissues throughout your body. Water also aids in cushioning and protecting your joints and assists in a wide varying of chemical reactions. So, yeah. it’s important.

But, you’ve seen the commercials. Athletes of all sorts also tend to guzzle down gallons of sports drinks. While these will be discussed in greater detail later, what’s important to realize now is that sports drinks are water with some key extra ingredients. Granted, the exact mix will depend on the product but most sports drinks include some sort of carbohydrate for fuel as well as a blend of electrolytes.

And it’s the inclusion of these minerals that make all the difference. As their name suggests, electrolytes are a special class of minerals that help conduct electrical impulses through your nervous system. This means that these minerals can have a variety of effects on your general health and athletic performance. Unfortunately, you lose lots of electrolytes in your sweat. As a result, intense exercise can cause potentially dangerous electrolyte imbalances.

When To Switch

In any discussion regarding fluid needs, then, it’s important to realize that sometimes water just won’t do it. But where’s that line? When should you switch over from plain old water to a fancy new sports drink?

As it turns out, the added boost of sugar and electrolytes is pretty much unnecessary. Until your workout exceeds an hour at a moderate-to-high-intensity, water can generally get the job done. In fact, throwing back a carb-rich sports drink during a short, relatively low intensity workout can mean that you’re actually taking in an excess of calories. Which is counterproductive.

For one thing – regarding fuel – your body has the ability to store a respectable amount of carbohydrates. Plus, more experienced athletes can actually increase the size of these storage banks as well as the efficiency with which they’re used.

But it’s also unlikely that you’ll be losing enough electrolytes to make a difference during shorter, less intense exercise bouts.

How Much Is Enough

Now that that distinction between water is (hopefully) clear, the next logical question to tackle has to do with actual dosage. How much water should you be drinking?

Of course, there’s the standard 64oz recommendation – generally split into eight 8oz glass spread throughout the day. Really, though, this guideline is, sadly, completely arbitrary and has absolutely no science behind it. That’s not to say that you’re going to hurt yourself by drinking 64oz each day, but it’s also not some magic number.

The reality is that, based on genetics, environment, diet, activity, gender, age, health conditions and a host of other factors, your hydration needs may be dramatically more or less than that standard recommendation. Based on this understanding, most experts suggest using the 64oz guideline as a starting part and simply drinking if you’re thirsty.

For athletes, though, this doesn’t really work. When you’re out for a run, by the time you feel thirsty, it’s too late. You’re already in the early stages of dehydration. The question for athletes, then, is how can you prevent dehydration and how can you rehydrate properly after a workout?

As stated, start with the standard 8×8 recommendation. While you’re exercising, though, drink 7 to 10oz of fluid for every 10 to 20 minutes of activity.  The exact numbers will depend on how much you sweat and how thirsty you feel.

What about recovery? While it takes some extra planning, the best way to judge your post-exercise hydration needs is to weigh yourself before and after your workout. Any amount of weight lost during that workout is typically from water. Sorry, you aren’t burning fat that fast. Drink 8oz of water for each pound that disappeared.

The Takeaway

Really, determining your fluid needs involves a huge amount of personal examination. There simply are no rules that will work for every person in every situation. Make it a habit to drink a minimum of 64oz of water each day, understanding that you might personally need more than that.

Don’t worry too much about sports drinks – laden down as they are with extra calories – unless your workout is intense and spans longer than an hour.