Hydration should be at the front of every runner’s mind, especially as temperatures begin to rise. Why is hydration important? What role do electrolytes play? How much should runners drink before, during, and after training? We’ll cover all this and more in today’s blog. Grab a drink and let’s dive in!
Why is hydration important for runners?
Water is found nearly everywhere in the body- blood, organs, joints, muscles, and even bones. When runners are adequately hydrated, they help their body with functions like temperature regulation, oxygen delivery, mental alertness, and removal of waste products. This in turn helps runners feel cooler, less fatigued, and more focused on the run. They also recover faster and reduce their risk of injury.
What happens when runners aren't adequately hydrated?
Runners typically lose fluid by breathing, sweating, and using the bathroom. Average fluid losses are about 1-4 lbs per hour when running. Fluid loss of only 1% of bodyweight (~1.5 lbs in a 150 lb athlete) has been shown to negatively impact performance. It's easy to understand, then, why a runner who doesn’t re-hydrate during an hour-long run might feel sluggish. Poorly hydrated runners can not only suffer from decreased performance, but serious conditions like dehydration and hyponatremia.
What are electrolytes and why do we need them?
Electrolytes (sodium, chloride, potassium, calcium, and magnesium) are minerals found in the body that help with many important functions including muscle and nerve function, blood pressure, and fluid balance. They are lost in sweat and urine, and when lost in large amounts can result in severe muscle cramping or hyponatremia. Sodium and chloride are lost in the greatest amount.
Runners can replenish electrolyte losses with sports beverages, salty foods, or gels, gummies, and other sodium-containing sports nutrition products. This is especially important for heavy and/or salty sweaters.
How to stay hydrated during the day:
- Monitor your urine (it should be a pale yellow color). Dark, amber-colored urine means you need to drink more fluids
- Carry a water bottle with you at all times
- Download a hydration tracking app
- Enjoy a glass of water with meals/snacks
- Enhance water flavor with fresh fruit and herbs
- Eat hydrating foods like watermelon, cucumber, bell peppers, oranges, fruit popsicles, and yogurt
- Avoid excess alcohol and caffeine
How to stay hydrated on the run:
- Begin well hydrated with pale yellow urine
- Drink 16-20 oz of water 2-3 hours before running
- Drink another 8-12 oz 15-30 minutes before running
- Drink enough to avoid losing more than 2% of your body weight from fluid. This can be calculated using your sweat rate (check out our coaching services for help with this). More general guidelines suggest consuming ~3-8 oz of fluid every 15-20 minutes (for reference, one medium mouthful of fluid is about 1 oz)
- Sip on sports drinks or add electrolytes if running for more than 60 minutes
- Know where to find fluids (water fountains, stores/restaurants, trusted neighbors, etc) ahead of time and bring cash or a credit card in case of emergency
- Remember that thirst isn’t always a good indicator of hydration. In some cases, runners may feel thirsty after they are already dehydrated. Distractions (music/podcasts, busy surroundings, focusing on form/pace, etc) can cause runners to miss or ignore their thirst signals.
- Drink 16-24 oz of fluid for every lb of body weight lost from fluid
- If dehydrated, drink sodium-containing beverages or pair water with a sodium-containing snack to help the body rehydrate. Snack examples include pretzels, pickles, crackers, salted fruits like watermelon, soups, chocolate milk, coconut water, or a fruit smoothie made with yogurt or milk.
- Avoid re-hydrating with alcohol, and be mindful of caffeine. Alcohol is a known diuretic that can cause athletes to urinate more (and halt rehydration). Caffeine is also a diuretic, but has more mild effects compared to alcohol, especially for those who regularly consume it.
Bottom line: proper hydration is an important practice for runners, especially in hot and humid conditions. By enhancing hydration techniques before, during, and after a session, runners can continue to run strong and healthy.
Need help creating a fueling and hydration plan for your next training cycle? Check out my 1:1 nutrition coaching services! A few simple changes in the kitchen might be the key to achieving your next PR.
- Karpinski, Christine, and Christine Rosenbloom. Sports Nutrition: a Handbook for Professionals: Sports, Cardiovascular, and Wellness Nutrition Dietetics Practice Group. 6th ed., Academy of Nutrition and Dietetics, 2017.