Hydration on the Run
Water and Electrolytes
During a long run or race we want to prevent dehydration, because losing over 2% body weight in water (via sweating) can hurt performance. Generally, an electrolyte beverage is going to be better than straight water, but there are a few things to keep in mind:
There is very big range of individual needs when it comes to electrolytes: some people sweat a lot, some sweat only a little. Some people have very salty sweat, and some don’t. The ranges of recommended water and electrolyte intake for athletes are so big that it doesn’t make sense to google search the answer. It makes sense intentionally discover what works for you and learning about your body.
Pre-Run
When pre-run hydration is adequate, it’s probably not necessary to hydrate during outings less than 60min unless the weather is really tough (hot and humid).
In general, aim to drink at least half your bodyweight in ounces of water (or other fluids) in a day, in addition to replacing the water lost via sweat during workouts. All beverages count except alcoholic drinks!
Your Body’s Signals
We can learn a lot about our individual hydration needs simply by paying attention to the signals from our body.
Cravings: Craving salty snacks after long runs or workouts may indicate the need to add (or increase) electrolytes during a session.
Salty Residue: People with a high concentration of salt in their sweat may notice a whitish residue on their skin after sweating through a workout or a run.
Water Loss: For heavy sweaters, or in really hot or humid weather, it may be helpful to record body weight (undressed) before and after a run to determine how much water is lost from sweat.
Your Fuel Choice
Some gels or other carbs have electrolytes in them, and in this case plain water with your gel may be adequate. Carb beverages usually have electrolytes in the formula. Some runners may need more electrolytes in addition to what’s in their fuel.
**Even if you’re not thirsty, the body needs water with gels (or gummies or other solid foods) to help with digestion.
You can make your own carb/electrolyte beverage by adding regular sugar and salt to water or juice. (Recipe and more info here from a Registered Sports Nutritionist.)
The Weather
It goes without saying that in hot and humid weather we will sweat more. It’s easier to remember to hydrate in these conditions because we’re so aware of the sweat. Where we can go wrong:
Cold weather where we hardly sweat at all.
Rainy weather when we don’t feel thirsty.
Very dry conditions when the sweat evaporates so fast we don’t even realize it.
Ideally the goal is to replace the water being lost via sweat during a run, so the weather plays a big factor. Adjust your hydration as needed. But remember: no matter the conditions, the body still needs hydration during long and/or intense exercise. No one really WANTS to carry a bottle or backpack while running, but it’s often a requirement for smart training and racing.
Experiment!
Pay attention to the signals your body sends during training and make adjustments as needed. It’s helpful to record the details of fueling and hydration in a training log, as well as any notable weather conditions while learning what your body needs. Hydration needs will change based on weather and pre-run hydration.
To dial in on your individual needs or for more information of any of these topics, I highly recommend consulting with a registered dietitian, sports nutritionist or qualified health professional.
Nicole Sifuentes is a full-time Running Coach for adults of all ages and abilities. She is a former professional runner and 2-time Olympian, and Certified Strength and Conditioning Specialist. Read more about her services, and schedule your free coaching consultation.