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Running Hydration: How to Properly Hydrate During Summer Training

Updated: Aug 18, 2023

Woman runner drinking water in the sun.

It’s common for runners of all lengths to sign up for fall races. Personally, it’s my favorite time of the year to race! In many parts of the country, the fall season brings cooler temperatures and breathtaking views. Some of the most popular marathons take place in the fall, including the Chicago and New York City Marathons, which are both part of the majors.

But it can come as a shock to many runners that despite the fall weather of race day, most of the training takes place in the hot and humid months of summer.

Whether you’re hitting the trails, tackling a summer or fall race, or simply maintaining your running routine during the summer months, staying hydrated is key to optimizing your performance and ensuring a safe and enjoyable run.

I’m going to cover why running hydration matters, summer hydration strategies, how to calculate your sweat rate, hydration products, and the importance of electrolytes:

As a coach, I often hear runners brag about never taking water with them on a run or only taking water on runs that are longer than x miles. Regardless of the miles or time that you’ll be out for a run, especially during the summer, it’s important to always have water with you!

I would rather an athlete have water with them and not need it versus the alternative.

Here’s why running hydration matters:

Temperature Regulation

Safety first! Running generates heat, and your body needs water to regulate its temperature. Proper hydration prevents overheating and reduces the risk of heat-related illnesses, especially during hot and humid weather.

Performance Boost

Dehydration can lead to reduced endurance, muscle cramps, and decreased energy levels. When you’re well hydrated, you have more stamina and can run longer distances with greater ease.

Muscle Function

Running hydration helps maintain proper muscle function, preventing early fatigue and optimizing your strength and power while running. Due to restrictions in blood pressure and perfusion pressure, dehydration leads to significantly reduced blood flow to the muscles.

Joint Health

Water plays a crucial role in the production of synovial fluid, a thin layer of fluid that both cushions and nourishes your joints. Additionally, it minimizes friction during joint movements. Dehydration can hinder the body’s ability to produce sufficient synovial fluid, leading to increased friction and potential discomfort.

Okay, I think now we understand the importance of running hydration, especially during the summer when most of us are sweating at a much higher rate.

Now, let’s discuss how to stay hydrated while training during the summer.


When it comes to summer training, you’ll want to find a hydration strategy that works for you.

Here are two popular hydration strategies:

1) General Hydration Strategy

2 Hours Before the Run

  • It’s suggested to consume between 16 and 24 ounces of water about 2 hours before your run.

  • You will want to take sips of water, don’t chug! Chugging can lead to cramping.

30 Minutes Before the Run

  • As you’re closer to heading out the door, you’ll want to consume another 8-16 ounces of water.

During the Run

  • The standard recommendation is to consume about 16 ounces of water per hour.

  • Again, it’s important to sip, not chug, during your run to prevent any adverse effects.

  • Calculate your sweat rate to find a more individualized approach (see below).

2) Other Hydration Strategy

There is another, much smaller school of thought that runners should only drink when they feel thirsty during an endurance event.

I struggle with recommending this strategy to clients, especially new runners, or first-time half/full marathon runners. The issue is that it’s entirely reliant upon the athlete being in tune with their body. The thrill and excitement of race day or even long runs can blur other aspects, causing them to forget to check in with themselves.

The other problem is that when you wait until you feel thirsty, you’re much more likely to chug. This often leads to cramping or other GI issues.

While I don’t generally recommend the second strategy, I fully believe that each athlete should find the hydration strategy that works best for them. As with most aspects of training for a race, you’ll want to practice your strategy throughout your training so that you’ve got it perfected by race day.

If the general guidelines leave you feeling bloated or cramping, try lowering the amount of water slightly next time, repeating until you get the right recipe.


If you want to get a specific measurement of how much fluid you lose through sweat to help you customize your hydration strategy, you’ll want to measure your sweat rate. The sweat rate is roughly what should be replaced per hour.

Woman runner sweating.

Obviously, you’ll want to test this prior to race day and if your calculation gives you a recommendation that causes you to feel too hydrated (i.e., stomach cramping, nausea), you’ll want to adjust and dial it back slightly.

The only equipment you need is a scale. Follow these steps:

  1. Weigh yourself before a run, naked.

  2. Do NOT hydrate after taking your weight or during the run, until step 4 is completed.

    1. OR if you do hydrate, you must measure the exact ounces of fluid you consume!

  3. Complete a 60-minute run.

  4. Weigh yourself immediately after running, naked. Do not urinate until your weight is taken.

Calculate sweat rate:

Pre-Run Weight – Post-Run Weight + fluid intake during activity (if applicable) = athlete’s individual sweat rate

For example:

Pre-workout weight: 140 lbs

Post-workout weight: 139 lbs

Fluid Intake: 16 oz

Exercise duration: 60 minutes

140 lbs – 139 lbs = 1 lb lost (16 oz) + 16 oz of fluid consumed = 32 oz (2 lbs) of sweat loss/hour.

In this example, the runner would need to drink around 32 ounces of water per hour to stay optimally hydrated.


It’s common for runners to avoid carrying water with them because they don’t know how to easily and comfortably.

Luckily, there are hydration products available that allow runners to carry water with them in a way that doesn’t get in the way while ensuring you stay hydrated.

Here are some options when it comes to hydration products you can take with you on your next run:

Hand-held Bottles

Hand-held water bottle for runners.

These bottles are typically shaped to curve in your hand, with a strap that allows you to keep your hand relaxed while keeping the bottle in place. You do not have to grip the actual bottle.

Some come with pockets for storage (your phone, keys, nutrition, or other valuables you’ll want with you during your run).

Available in different sizes (i.e., 16 oz, 32 oz, etc.).

Hydration Vest/Pack

Runners with hydration vests.

If you want to be hands-free during your run, the hydration vest/pack is for you! These provide comfort on your run by keeping your hands free while allowing you to generally carry more water with you than hand-held bottles.

Most vests/packs come with tons of storage/pockets to store valuables and/or nutrition. Some come with bottles, others come with a bladder.

Available in different sizes and different-sized bladders depending on how much water you want to take with you.

Hydration Belts

Hydration belt with water bottles and storage.

Belts also offer the benefit of storage/pockets, as with hand-held bottles and vests/packs, and keep your hands free like the vests/packs.

Belts strap around your waist and are adjustable, allowing you to place it where it’s most comfortable.

Most come with 1 or 2 water bottles that you can easily remove and put back in place during your run.


If one of these options doesn’t jump out as the right product for you, I recommend heading to your local run specialty store. Most run specialty stores will carry hydration products that you can try on and test out (run around the store!).

Each category listed above has many different options and features to consider.


Electrolytes are essential minerals – like sodium, calcium, or magnesium – that play many key roles in the body, such as:

  • Regulate muscle contractions

  • Keep one hydrated

  • Help balance pH levels

  • Control nervous system functions

One way you lose electrolytes is through your sweat. When you’re done with a long run, especially in the hot or humid summer months, you may see a white ring around your hat or on your clothes. This means you’re likely losing a lot of sodium.

Runner grabbing water during a race.

There’s long been a debate regarding the need for added electrolytes.

There’s the thought that if you’re eating a nutritious diet, especially whole foods, you’re likely getting all your needed electrolytes. Even so, during the summer when you’re running longer with higher humidity and heat levels, it may be beneficial to add electrolytes to your daily routine.

There are many products available as electrolyte replacement options. You’ll want to try different types and flavors to nail down what works for you. It’s important to read labels for information on what is being provided, such as added sugar, electrolyte levels, etc.

During runs longer than 90 minutes, you will want to consider a product with added carbohydrates. For runs less than 90 minutes, carbs won’t be needed.

Electrolytes come in powders or tablets that you simply add to water, or you can buy pre-made drinks. Again, I recommend visiting a local run specialty store and sampling a few different products that you can try during training to ensure you’re confident in your hydration plan by race day.

I get it – carrying water can feel inconvenient and at times, cumbersome. But it doesn’t have to feel that way!

Runner drinking water on the beach.

As I shared above, there are various types of products available that will allow you to carry your water with ease. Ultimately, when you’re training in the summer, carrying and consuming water during your runs will keep you safe and cool. Even more than that, proper hydration keeps you running stronger and longer!

If you’re struggling to find the right hydration strategy, schedule a free Discovery Call here. We can chat about your goals as well as what obstacles you’re facing, and I’ll share a few tips on how to perfect your hydration plan.

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