7 Smart Ways to Rehydrate After an Intense Workout

If you feel like your TikTok and Instagram feed has recently blown up with ads for rehydration tablets and mixes from trendy brands like Nuun, LMNT, or Liquid IV—you’re not alone. And it probably makes you wonder: Is chugging a plain old glass of water really the most efficient way to keep dehydration at bay? Especially if you’re hot and sweaty after a tough workout?

Before we get into that, though, it’s important to understand why your workout triggers the need to maximize your hydration. One big reason? Sweat. As your body temperature increases during exercise, your body responds by sweating, which then evaporates to cool you down. The longer you exercise, the more you sweat, and the more fluids and electrolytes—other components of sweat—you’ll need to replace.

You sweat more in hot and humid conditions, which makes hydration super important in warmer temperatures, but it’s also possible to become dehydrated after workouts in cooler weather, Riana R. Pryor, PhD, ATC, director of the Hydration, Exercise, and Thermoregulation (HEAT) Laboratory at the Center for Research and Education in Special Environments in the University of Buffalo, tells SELF. That’s partly because your thirst tends to be less pronounced when it’s cooler, which makes you not want to drink as much water after a cold weather workout, she says.

So whether we’re talking about a workout in the blazing summer sun, a mild fall day, or even in the deep chill of winter, hydrating afterward is vital. But what’s the best way to do it? We chatted with a hydration expert and a registered dietitian/personal trainer who works with endurance athletes to break it all down. Below, everything you need to know about what contributes to proper hydration after exercising, signs you may be dehydrated, and some actionable ways you can make sure you’re maximizing your hydration after your next tough workout.

What do we need to hydrate properly?

When thinking about hydration, you may focus solely on the water aspect. After all, you’re losing fluid, right? Though that is true, water isn’t the only thing in your sweat that you need to replenish.

Your sweat is also made up of minerals called electrolytes, which include sodium, magnesium, and calcium chloride and bicarbonate, Holley Samuel, MEd, RDN, CPT, registered dietitian and founder of Holley Fueled Nutrition, tells SELF. These electrolytes are vital in your body, since they help balance the amount of water in it and move nutrients into your cells and waste out of them, per the US National Library of Medicine. Out of all of these electrolytes, sodium—a.k.a. salt—is the one lost in greatest concentrations when you sweat.

That means in order to remain optimally hydrated, you should take in a balance of water and electrolytes, Samuel says. It’s especially important to replace sodium, since not only is it lost the most in sweat, but it also plays the most important role in your body’s fluid balance.

If you don’t get enough fluids and electrolytes, you risk dehydration, when your body doesn’t have enough fluids to function normally, per the Mayo Clinic. Symptoms you may experience if you’re dehydrated include lightheadedness, GI distress, muscle cramps, and nausea, Samuel says.

What are signs you need to hydrate?

For adults, the two main indicators that your body needs more hydration are thirst and urine color. You generally start to feel thirsty when you have lost about 2% of your body weight due to water loss, Pryor says.

So for instance, if you weigh 160 pounds, you’ll begin to feel thirsty once you lose 3.2 pounds of water, Pryor says. Of course, you won’t have access to a scale while working out to see if you’ve reached that threshold, so staying attuned to your body’s thirst signals becomes important. Meaning whenever you start to feel the need to drink while working out, do so!

Urine color is also an important indicator of your hydration status. Someone who’s well hydrated will have light-colored urine, similar to lemonade, Pryor says. If you’re dehydrated, you’ll have darker-colored urine, like apple juice.

What are the best ways to rehydrate after a sweaty workout?

You can avoid dehydration symptoms long before they start by making sure you’re hydrating before, during, and after your workout with water-dense foods and drinks. Here are some ways to ensure you’re properly replenishing fluid loss after a tough workout.

One of the best ways to rehydrate after a sweaty workout is to play the preventive game beforehand: Go into your workout optimally hydrated.

“I always recommend trying to get some water in at the beginning of the day so that you’re not trying to make up for it and chug at the end of the day,” Samuel says.

As for how much to drink? The American College of Sports Medicine (ACSM)’s hydration guidelines recommend drinking 17 ounces of fluid two hours before exercise.

During exercise, you should drink at the start and throughout your workout at regular intervals to replace fluids lost from sweating. How much you need to drink during your workout depends on a variety of factors, including your sweat rate and generally how thirsty you feel. The ACSM doesn’t provide exact numbers, since it’s so individualized, but you can consider eight ounces per hour a minimum amount. But again, we’ll reiterate that rather than shooting for a set amount, it’s important to drink based on how thirsty you feel. (In fact, drinking more than you need all at once can lead to a serious but rare condition called hyponatremia, which occurs when the sodium in your body becomes diluted by too much plain water.)

Shoot to replace 100% to 150% of your total losses, Pryor says. For instance, if you lose one liter (34 ounces), you should try to take in 1 to 1.5 liters of fluid (34 to 51 ounces).

“It’s generally suggested to consume slightly more than what you lost because your body doesn’t absorb all the fluid you drink,” Pryor explains.

One way you can figure out how much fluid you lose during exercise is to weigh yourself before and after your workout. The difference is the amount of water you lost. Once you get that number, try Pryor’s calculation: Multiply that by 16 to get fluid lost in ounces. Then multiply that by 1 and 1.5 to get your range in ounces. For instance, if you lost 32 ounces (or two pounds) during your workout, you should aim to take in 32 to 48 ounces afterward. (Of course, only try this tip if weighing yourself or having a scale around is not triggering to you in any way.)

Believe it or not, chugging down glasses of water postworkout doesn’t do as much to hydrate you as you may think. Instead, taking frequent sips—before, during, and after exercise, is what will really help, Pryor says.

This allows your body to better retain water, which will aid in transporting electrolytes to where they need to go. If you’re gulping down glasses of water at once, then it’s going right through you—you’ll be peeing it out—so it doesn’t do the work of hydrating you. It might even pull out nutrients from your body along with it.

Plus chugging water can lead to not-so-pleasant effects like extreme fullness or an upset stomach. “People don’t want to drink more than half a liter at once,” says Pryor, who recently completed research on this topic. Sticking to sipping 16 ounces every 30 to 45 minutes throughout the day is what’s going to be most helpful.

As we mentioned, there are two parts to hydration: water and electrolytes. If you’re working out for more than an hour, especially in a humid environment, or if you are a salty sweater—here’s how to tell if you are one—you could benefit from drinking some electrolytes with your water.

According to Pryor, if you’re losing about 1 to 2 liters of sweat per hour, that translates to about 1.6 grams (1,600 mg) of sodium per liter. Knowing those numbers can help guide you when thinking about which electrolyte packets or sports drinks are right for you.

For example, a Gatorade Thirst Quencher has 160 milligrams of sodium per 12-ounce serving, while a packet of Liquid IV electrolyte power has 500 milligrams in one serving. Products run the gamut in the amount of sodium they have, so you’ll want to choose one that’s best for you. For instance, if you are exercising for an hour or more, electrolyte packets with higher sodium content may be a better fit for you than a sports drink like Gatorade, which has less.

“General nutrition recommendations are to take anywhere from 300 to 600 milligrams of sodium per hour that we’re exercising,” Samuel says. “Some people are saltier sweaters—like if your sweat really burns your eyes, if you have a lot of white on your clothes after exercising, or if you can just feel a lot of salt crystals on your skin. Those people might need upwards of 1,200 milligrams of sodium per hour just to replace what they’re losing.”

Remember, sodium is the most important electrolyte for replacement in these cases. So focus on that in your electrolyte drinks or packets—the other electrolytes they provide should be enough to replace the electrolytes you lose in lesser amounts.

Another quick way to rehydrate postworkout is with a smoothie. Smoothies are particularly a good choice if you exercise for less than an hour—meaning replacing larger amounts of sodium (like you’d need with an electrolyte packet or drink) likely won’t be as much of a concern. They’re also great for fueling up on other nutrients your body needs postworkout, such as protein and fat, especially for those who might not have a big appetite after exercise.

To make the most of your smoothie, add foods that are naturally high in electrolytes, like watermelon, banana, and dates, Samuel says. You can also incorporate some leafy greens and coconut water, which are excellent sources of potassium.

“Putting fruit into a smoothie, like bananas or dates, that are high in potassium and adding some sea salt can help you rehydrate,” she says.

If you have trouble remembering to take frequent sips after your workout, Pryor suggests eating foods high in water content, such as cucumbers, peppers, broccoli, lettuce, and watermelon, to help replenish your fluids. Zucchini, cauliflower, strawberries, and celery are also very hydrating vegetables and fruits to munch on, according to the Cleveland Clinic.

Add these foods to your salads, smoothies, or just snack on them throughout the day to increase your water and mineral intake.

“Try putting some sea salt on your watermelon. That would help with replacing sodium and potassium because watermelon naturally has a lot of potassium,” Samuel says.

Eating snack foods that are a little higher in sodium can help your body retain water. Consider eating some pretzels, salted nuts, cheese and crackers, and beef jerky, while also drinking water, Samuel says. You can also enjoy saltier meals, like sushi with soy sauce or a tuna sandwich.

“Most people can replace electrolytes lost in sweat simply by eating a wide variety of healthy foods,” Pryor says.