Are ‘Cold Plunge’ Ice Baths Good for You?

Are you thinking of taking the plunge into … well, cold plunging? If so, there are some things you need to know before making regular dips in icy water part of your workout or wellness routine.

Because while there may be benefits to cold-water immersion, it also comes with risks. We asked sports medicine physician Dominic King, DO, for some tips on how to safely take an ice bath.

What is a cold plunge?

A cold plunge is exactly what it sounds like: A dip into an icy bath. (And, yes, an icy bath is exactly what it sounds like, too. You could literally be chilling in the tub with floating ice cubes. BRRRR!)

A cold plunge may also be called cold therapy or cold-water immersion.

A tub filled with cold tap water can be just low enough on the temperature front to achieve some goals of a cold plunge, says Dr. King. For a frostier experience, some go even colder by adding a few large bags of ice to the water.

Cold plunge benefits

So, why would someone want to get into an ice-filled tub? Here are a few potential health benefits of cold plunges.

• Sore muscle recovery: Slipping into frigid water may help reduce muscle soreness, especially after a tough workout. That’s because the cold constricts blood vessels, temporarily reducing swelling and inflammation to aid recovery.
• Mood enhancement: Studies point to potential mental wellness benefits from taking an ice bath, with reductions in stress and gains in alertness and focus. “Some people feel it’s a very helpful mental meditation for them,” Dr. King says.
• Improved sleep quality: There’s evidence that cold water immersion therapy can help you sleep better and reduce tossing and turning at night, particularly if you’re an endurance athlete.
• Protection from illness: Can freezing your buns off in cold water for a few minutes keep you from getting sick? Evidence is preliminary, but some research suggests cold therapy might support immune system function.
• Reduced body temperature: If your body is running hot after a grueling workout, a cold plunge can quickly bring your core temperature back down. (This method is often used in sports medicine as emergency treatment for heat-related illness.)

“There’s no doubt that some people get great relief from using ice baths,” says Dr. King. “We’ve seen people get physical, mental and functional benefits from this kind of cold therapy.”

Risks of cold plunge therapy

Soaking in an ice-cold tub does come with a few potential dangers — particularly if you don’t follow safety guidelines. (More on that in a moment.) Risks include:

• Hypothermia: Prolonged exposure to cold water can lower your core body temperature, leading to hypothermia. This occurs when your body loses heat faster than it can produce it, causing shivering, confusion and even unconsciousness.
• Skin and nerve damage: Overly long plunges may cause frostbite or skin damage. The possibility of this increases as the temperature of the water drops, too.
• Breathing difficulties: Cold water can trigger rapid, uncontrolled breathing (hyperventilation). This can be dangerous if it leads to dizziness or fainting, especially while in the water.
• Cardiovascular stress: When cold water constricts your blood vessels, it raises your blood pressure and forces your heart to work harder. This can be dangerous for people with heart conditions, hypertension or elevated stroke risk.
• Numbness: Extended exposure to cold water can lead to numbness and reduced motor control, making it difficult to exit the water safely. In extreme cases, it can result in cold-induced muscle cramps.

The negative effect on muscle gains

If you’re trying to bulk up and build muscle, you might want to think twice about cold plunging after a workout. The reason? The way cold therapy reduces inflammation can also silence the muscle-building signals your body uses after strength training.

“If not timed right, cold therapy can interfere with muscle gains,” warns Dr. King.

That’s especially true if you do a plunge within four hours of a muscle-building workout. (It may still be beneficial for recovery purposes on rest days between workouts.)

How to safely cold plunge

As you might imagine, taking an ice bath comes with safety guidelines, particularly regarding time and temperature. (Remember how it ends for Jack in “Titanic”? You want to avoid that.)

Here’s what you need to focus on.

• Check the temperature. A plunge should be cold — but not too cold. Avoid going below 40 degrees Fahrenheit (4 degrees Celsius). For beginners, a safe starting range is 50 to 59 F (10 to 15 C). Use a thermometer to make sure you’re in a safe zone.
• Keep it quick. A session should never go longer than five minutes. Beginners should limit their sessions to a minute or two. “Start slow and see what your body can tolerate before staying in longer,” advises Dr. King.
• Listen to your body. If you experience lightheadedness or discomfort beyond just the sensation of being cold, get out of the water. “Cold water can become dangerous quickly,” states Dr. King. “Don’t try to push through what doesn’t feel right.”
• Warm up. Once you’re out of the icy water, focus on bringing your body temperature back up. Dry off quickly and put on warm clothes. You may even want to try sauna therapy after taking a cold plunge.

Beginners should only look to cold plunge once or twice a week. As you get more accustomed to the shock of a frigid dip and see benefits, you can look to add in days. Some people can tolerate a daily plunge.

Who should avoid cold plunging?

Before you take a cold plunge, Dr. King urges you to talk to your healthcare provider about whether it’s safe for you. That’s particularly true if you’re dealing with any of the following:

• Heart disease
• High blood pressure
• Diabetes
• Pregnancy
• Peripheral neuropathy
• Poor circulation
• Venous stasis
• Cold agglutinin disease

“Cold plunges are an option to consider in certain situations, but they’re not essential to a training program,” says Dr. King. “If you want to try it and it works for you, great — but it’s not for everyone.”