Are You Drinking Too Much Water When You Exercise?

Undereating carbohydrates
Photo Credit: Bonninstudio

January 26, 2021

By Isadora Baum

When it comes to dietary villains, salt is almost always on the Most Wanted list. It’s so ingrained in us that salt is bad and that we’re probably eating too much, we might be missing symptoms of low sodium in our diets. That’s right: It’s possible to get too little salt. One risk factor: Over-hydrating during rigorous exercise.

But, first: What is salt?

Salt is composed primarily of sodium and chloride. It’s the main way that we consume sodium; 90% of sodium we eat is in the form of sodium chloride. And we need sodium to help keep the body’s fluid levels balanced and to optimize nerve and muscle function.

Experts at the Mayo Clinic recommend eating one teaspoon of salt, which contains approximately 2,300 mg of sodium. The American Heart Association prefers 3/4 teaspoon, or about 1,725 mg. Either way, it’s tricky to track sodium since it doesn’t all come from the salt shaker. Sodium is naturally occurring in certain foods (like celery!) and it’s also an additive in most processed foods.

Are you sodium deficient?

For most people, a healthy diet provides plenty of sodium; in fact, many Americans have excess sodium in their diet. But some of us are at risk for sodium deficiency. Athletes and people with certain medical conditions or who take some medications are at risk for hyponatremia, says Pam Nisevich Bede, MS, RD, sports dietitian with EAS Sport Nutrition. “This is a condition that occurs when sodium in the body is depleted and not replaced, but water intake remains high, diluting sodium stores and leading to serious consequences.”

When there’s inadequate sodium in the blood, water pours into cells to compensate, adds Lauren Popeck, R.D. at Orlando Health. This excess fluid, if not treated, can lead to brain impairment, and even death, over time.

Dr. Partha Nandi, creator and host of Emmy-award winning talk show “Ask Dr. Nandi,” says symptoms of sodium deficiency include: nausea and vomiting, decreased appetite, headache, fatigue, confusion, and muscle cramps.

Heart, kidney, and liver disease can all lead to excess fluids, which can upset the body’s sodium balance. Antidepressants, pain medication, and diuretics can cause frequent urination and perspiration.

Excessive exercise, paired with excessive hydration, can also be dangerous. But, the good news is, you don’t have to give up your HIIT workout. Here’s a simple way to determine whether you’re drinking too much while exercising: “If you finish a workout and gained weight, chances are you over-drank,” Bede notes. “Next time out, pay attention to thirst and weight and personalize your fluid intake to better meet your body’s needs.”

Here’s what to eat if you have a sodium deficiency.

There’s a reason runners receive bananas after races: Sodium’s partner in maintaining the body’s fluid balance is potassium. “Eating a high-quality diet that’s rich in potassium is helpful to achieve sodium balance,” Popeck says. “Top sources of potassium include avocado, lima beans, white beans, bananas, yogurt, sweet potatoes, spinach, and Portobello mushrooms. The goal is to get 4,700 mg potassium per day.” An avocado has about 1,067 mg, a large sweet potato has 855 mg, a cup of coconut water has about 600 mg, and a banana has about 485 mg.

Unless your doctor advises against it, you can enjoy a few salty foods as well. These staples are rich in sodium and actually good for you, so add them in small portions: