Should You Drink Water While Running?


Water. We can’t live without it, and we shouldn’t be running without it, either.

But should you drink water while running? It can be a pain to carry it with you, so many runners are tempted to leave it behind and just hydrate before and after.

We get it. Water can weigh you down, whether you are wearing a pack, waist belt, or a bottle in one hand. But if you are running long, in hot and humid conditions, or sweat a lot, you really should be drinking water while you run.

Here’s what you need to know including why it’s important, some easy ways to carry a lot of water with you, how to tell if you’re drinking enough, and tips to stay hydrated so you can perform at your best.

Why Is It Important to Stay Hydrated During a Run?

The more you exercise, the more you sweat. It’s a natural process that happens even when the weather isn’t hot—it’s your body’s way of keeping itself cool from the inside out. If you don’t replenish the fluid you lose while running, it can have some nasty consequences.

The more dehydrated the body gets, the more your performance suffers. Even mild dehydration can lead to headaches, dizziness, nausea, and muscle cramps. Severe dehydration can begin to have adverse effects on your cognition, impairing your performance.

Becoming too dehydrated can cause the body to overheat, which means you’ll risk heat stroke.

If you don’t hydrate properly, you’ll be ruining your performance but also endangering your health.

Should You Drink Water While Running?

Yes, you definitely should be drinking water while you’re running.

You don’t need to drink the entire run, but you should have an idea of when to drink so you can make sure you avoid dehydration.

When Should You Drink Water?

Whether or not you need to drink before your run depends on a number of factors. If you’re going for a short run of 30 to 45 minutes and you’re already well-hydrated—clear or pale yellow urine—then you may not need to.

If you’re not well-hydrated—darker colored urine—then you should drink between 12 and 20 ounces of water in the few hours before your run, so you don’t begin your run dehydrated. Aim to finish the last of it about 15 minutes before you run.

However, even if you’re well-hydrated, consider the weather before you go for your run. If it’s hot or humid, you’re likely to lose more fluid during your run. In this case, hydrating before your run is a good idea.

If you’re running for longer than an hour, drink some water every 15 to 20 minutes during your run. Most running watches come with an alarm or timer system that you can set every 15 to 20 minutes to remind you to drink.

How Much Water Should You Drink?

Some people sweat more than others, so everybody’s fluid needs differ. To accurately work out how much water you should drink during your run to stay hydrated, you must work out your sweat rate.

We advise doing a “sweat rate run” to figure it out. The first step is to weigh yourself before the run. It’s best to do this without clothes, so there’s no extra weight. Take note of this number and then head out for your run.

Run as you usually would, but limit your time to an hour. Also, take note of how much you drink during your run. Once you’re finished, weigh yourself again and note the number.

Subtract your “after” weight from your “before” weight to determine how much you lost during the run. Let’s assume that you lost a pound—16 ounces—in an hour of running. That means you lost 16 oz of fluid through sweat during your run.

Add the amount of water you drank—let’s say 10 ounces—and that’s how much water you need to drink per hour to stay properly hydrated. In this case, you’ll need 26 ounces of water an hour, which equals 6.5 ounces every 15 minutes.

If an hour-long run is too long, stick to 30 minutes. You’ll calculate it per half-hour instead, but it’s still easy to work out your 15-minute drinking requirement. Also, remember that you’ll need to up that 15-minute rate if the weather is hot.

Should You Only Drink Water on a Run?

Plain water is the best thing to hydrate you on runs. Sports drinks often have sugar, which can add calories and spike your blood sugar.

However, once you hit an hour or more of running, your body isn’t just losing water. It’s also losing electrolytes, vital minerals the body needs to function. Lose too many electrolytes through sweat, and you’ll start experiencing unpleasant symptoms like nausea, muscle cramps, and even unexplained confusion.

It’s a good idea to take an electrolyte supplement along for each hour of running you plan to do. You can easily slip these tablets into your water to replace the lost electrolytes.

At the hour mark, your body also begins to run low on glycogen, the stored energy in the muscles. At this point, you may want to consider a sports drink that has some easily-absorbable carbohydrates in it.

Make sure that when choosing a sports drink, it’s not loaded with unhealthy sugar and fillers. Ideally, you want to find one that offers around 14 grams of carbs and electrolytes. Avoid carbonated drinks, as they can upset your stomach.

How Can You Drink Water While You Run?

Thankfully, there are plenty of ways to drink water while you run. You don’t need to worry about stopping to fill up a tiny, easy-to-carry water bottle along the way. These easy solutions help you to stay hydrated throughout your exercise.

Hydration Packs

A hydration pack is the most convenient way to carry a lot of water on a run. It’s a hands-free system that looks like a small backpack. Most have both a bladder, which can hold more water, and space for one or two water bottles.

Some are limited to one or the other—a bladder or water bottle holder. If you prefer the classic water bottle but don’t like carrying them in your hand, a hydration pack is still a good choice as you can run freely.

Hydration Belts

Hydration belts are handy because most of them have some storage space as well. They come in various sizes and designs, but they all have space for one or two water bottles. Some carry them on the hip, others around the back.

The biggest issue with belts is that they can bounce. If they’re slightly loose or wiggle loose as you run, you might find that they begin to jiggle a little as the water in the bottles sloshes around.

They’re often more convenient than hydration packs, though, because they’re easier to get on and off, as well as to refill. If you’re getting a running belt to store gels and personal items, you may as well go for a hydration belt.

Handheld Water Bottles

The most classic way to carry your water. Today’s handheld water bottles are more technologically-advanced than older ones. Many are designed ergonomically, to fit the contours of the hand and come with wide openings for easy refilling.

Most of them also come with a handstrap and storage. Not only does this insulate the bottle, but lets you strap it and run without needing to grip it tightly. Relax your fingers, and you’ll find that you can run more freely.

Some also come with storage space for small things, like credit cards, a gel, or a key. Most can’t fit a cellphone, so you may still need a running belt depending on what you want to carry.

Water Stations on Running Routes

During a race, there are likely to be water stations along the route. You can grab a cup of water as you go. They usually use disposable cups, so you can keep running, finish your water, and simply drop the cup when you’re done.

During training runs, you can recreate this by planning a route with water fountains. Check parks and bike paths to see if these are available near you.

With some pre-planning, you can also drop water along the route you plan to run. Just take your car out and hide some bottles in bushes or behind trees.

Another options is to create a short 1-3 mile loop from your house or car. Leave plenty of water there and keep running that loop for as long as you are planning to run.

How to Tell if You’re Not Getting Enough Fluids

Unsure if you’re dehydrated or not? Here are some signs and symptoms to look out for when you’re running and even throughout the day when you aren’t exercising.

  • Thirst: The first feeling of thirst means your body is already dehydrated. Ideally, you want to stay so hydrated that you don’t feel thirsty.
  • Dark Urine: Dark-colored urine indicates dehydration. Light-colored, almost clear urine indicates that you’re taking in enough fluid to flush everything through.
  • Dry Mouth & Skin: Often, the first sign is chapped lips. Your skin and mucosal linings are the first things to suffer when you’re dehydrated.
  • Fatigue: If your cells aren’t getting enough water, they can tire easily. Low energy levels and feeling tired and sluggish could be a sign of dehydration.
  • Headache: With a reduction in fluid in the body, blood doesn’t flow so easily. This can increase blood pressure as the heart has to pump harder to push the blood around, leading to a pounding headache.

Tips for Staying Hydrated on Your Run

With just a bit of preparation and thought, you can boost your hydration and your performance. Here’s how to stay hydrated during your run.

Start Hydrating Before Your Run

Although it’s not absolutely necessary if you’re already well-hydrated throughout the day, you can pre-hydrate by drinking around 16 to 20 ounces of water about 2 to 3 hours before your run.

Then, about 15 to 20 minutes before your run, drink 8 to 10 ounces. You’ll start your run well-hydrated, but not with a full bladder, which is the optimal way to begin. Then it’s just a matter of maintaining that hydration level as you go.

Plan Your Route

If you don’t want to carry too much water, you can always plan your route to pass a water fountain so you can fill up along the way.

Keep in mind that this means stopping for a minute or so to fill up, which could influence your training metrics if you’re keeping a close eye on them.

Monitor Your Fluid Loss

Try to be mindful of your fluid loss during the run. If you’ve already calculated your fluid loss, you’ll know how much you should drink and how often. But try to be aware of how you’re feeling throughout the run.

Do you feel like you’re sweating more than usual? Are you unusually thirsty? Is there wind or humidity? All of these things can influence how much fluid you lose, so it’s wise to check in with yourself and see how you’re feeling.

Watch for Signs of Dehydration

In the same vein, monitor yourself for the typical signs of dehydration. Feeling thirsty is the first sign of being mildly dehydrated, so take a drink any time you start to feel thirsty.

If you experience any other dehydration symptoms, replenish fluids immediately. Electrolytes may be necessary, so it’s a good idea to always carry some with you.

In most cases, rehydrating and giving your body some electrolytes will help. But if you don’t start to feel better soon, it might be in your best interest to stop, rest, and rehydrate properly when your body is relaxed and in a cool place.

Photo of author


Ben is an avid road and trail runner, and has completed multiple marathons and ultras. A former running store owner, he now shares his knowledge and experience writing these articles.

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