Quick answer
A cold plunge tub is a basin designed for cold water immersion, often kept between 50 and 60°F. It may ease muscle soreness after exercise, but evidence for other health benefits is limited, and it is not suitable for people with certain health conditions.
- Start with warmer water and short sessions, keep your head above water and do not plunge alone.
- Check with a doctor first if you have heart disease, high blood pressure or other health conditions.
- High-end tubs chill the water with a refrigeration system, while simpler models rely on added ice.
The practice of using cold water as a healing tool has been around for thousands of years.
Today, the modern embodiment of this ancient technique is called a Cold Plunge Tub.
What is a cold plunge tub?
A Cold Plunge Tub is a basin designed for cold-water immersion therapy, often kept between 50-60°F. It may ease muscle soreness after exercise. Evidence for other health benefits is limited. Not suitable for individuals with certain health conditions like cardiovascular disease.
In this guide, you’ll learn everything you need to know about a cold plunge tub.
What Is a Cold Plunge Tub?
A Cold Plunge Tub is a large basin or tub filled with cold water, often ranging from 50 to 60 degrees Fahrenheit, which is approximately 10 to 15.5 degrees Celsius.
Cleveland Clinic advises against going below 40 degrees Fahrenheit (4 degrees Celsius). It suggests beginners start at 50 to 59 degrees Fahrenheit (10 to 15 degrees Celsius).
The cold plunge tub is designed specifically for the practice of cold-water immersion, a form of therapy used for various health benefits.
Sessions are short. Mayo Clinic Health System says people typically start with 30 seconds to a minute and work up to five to 10 minutes. Cleveland Clinic is stricter and says a session should never go longer than five minutes.
The exact timing is based on the temperature and your tolerance.
The idea is that a short, controlled exposure to cold triggers responses in the body that may help with recovery after exercise.
Different Names for a Cold Plunge Tub
Depending on where you are in the world or the context, Cold Plunge Tubs can also go by other names.
Names such as:
- Cold Tub
- Ice Bath
- Recovery Bathtub
- Cold Water Therapy Tub
- Chill Pool
- Cryotherapy Tub
- Hydrotherapy Tub
Each name reflects a different aspect of the cold-water immersion experience, but they all refer to the same essential concept: a tub designed to hold very cold water for therapeutic use.
Types of Cold Plunge Tubs
There are several types of Cold Plunge Tubs available, each with its unique features and benefits:
- Standalone Cold Plunge Tubs. These are freestanding units, often made of stainless steel or acrylic. They typically come with a built-in chiller to maintain the water temperature.
- In-Ground Cold Plunge Tubs. These are built into the ground like a small pool and are usually installed as part of a larger spa facility.
- Portable Cold Plunge Tubs. These are lightweight, often inflatable, and can be filled and emptied as needed. They don’t typically have built-in chillers, so ice may need to be added to achieve the desired water temperature.
How Does a Cold Plunge Tub Work?
A Cold Plunge Tub functions by providing a regulated and controlled environment for cold-water immersion therapy.
Its primary purpose is to maintain a consistently low temperature for therapeutic use.
In high-end models and commercial installations, a Cold Plunge Tub is typically equipped with a built-in refrigeration system that continually cools the water. This system functions much like a household refrigerator.
A compressor squeezes a refrigerant gas, which heats it up. The hot gas gives off that heat to the outside air and turns into a liquid.
The liquid then passes through an expansion valve, where it becomes very cold. It absorbs heat from the tub water, which lowers the water temperature.
It then flows back to the compressor, and the cycle repeats, maintaining a consistently cold temperature in the tub.
Simultaneously, a pump is often used to circulate the water, ensuring an even distribution of cold throughout the tub. Some systems may also feature an air blower for hydrotherapy benefits.
In contrast, simpler models, like portable or inflatable cold plunge tubs, do not usually have a built-in cooling system.
Instead, the temperature is lowered by adding ice to the water.
The amount of ice needed will depend on several factors including the initial water temperature, the size of the tub, and the desired water temperature.
Here is a good video that explains how ice baths work:
Cold Plunge Tub Benefits
Cold-water immersion triggers several responses in the body. Some of the claimed benefits are better supported than others.
Here is what the evidence says:
- Enhanced RecoveryCold water after hard exercise can reduce muscle soreness. Mayo Clinic Health System says less muscle damage leads to less inflammation, which reduces soreness and helps restore physical performance the next day. There is a catch for strength training. Mayo says cold water after resistance training may hinder long-term improvements in strength, muscle growth and performance.
- Mood and Stress.Many people say they feel more alert after a cold plunge, but the research is limited. Harvard Health reports that a 2025 review of 11 studies found ice baths reduced stress levels, although not until 12 hours after immersion. The same review found no consistent evidence that immersions boosted mood.
- Immune Effects.The evidence here is weak. The 2025 review reported by Harvard Health found no consistent evidence that cold water immersion boosted immunity.
- Improved SleepThe evidence is mixed. In the 2025 review, men reported sleeping better after ice baths but women did not.
- Circulation.Cold water narrows the blood vessels that supply the skin and raises your heart rate and blood pressure, which makes the heart work harder. Harvard Health says not to count on any heart-related advantages for now.
Cold Plunge Tub Negatives
Despite their numerous benefits, Cold Plunge Tubs aren’t without potential drawbacks and risks:
- Hypothermia. Immersion in cold water can significantly lower body temperature. If the water is too cold, or if the immersion lasts for too long, there’s a risk of hypothermia. Symptoms include shivering, fast breathing, tiredness, confusion, and loss of coordination.
- Cold Shock. Getting into cold water triggers a sudden, rapid increase in breathing, heart rate and blood pressure, known as the cold shock response. The American Heart Association warns that a person can drown within seconds if they involuntarily gasp while their head is under water. Keep your head above the water and do not plunge alone.
- Health Risks for Certain Individuals. Cold Plunge Tubs can pose risks for people with certain health conditions. For example, the rapid cooling and subsequent rewarming of the body can put stress on the heart, potentially leading to heart problems in susceptible individuals.
- Maintenance and Upkeep. Maintaining a Cold Plunge Tub can be time-consuming and expensive. Regular tasks may include cleaning the tub, changing or treating the water to maintain cleanliness and balance, and monitoring the water temperature.
Who Is a Cold Plunge Tub For?
Cold Plunge Tubs are generally suitable for healthy adults who want to boost their wellness routine.
They are particularly popular among athletes and fitness enthusiasts for their recovery benefits.
Some people use cold plunges to wind down or manage stress, although the evidence for those benefits is limited.
Who Is a Cold Plunge Tub Not For?
While Cold Plunge Tubs can be beneficial for many people, they aren’t suitable for everyone.
Certain individuals should avoid cold water therapy or proceed with caution.
Cleveland Clinic says to talk to your healthcare provider first if you have heart disease, high blood pressure, diabetes, peripheral neuropathy, poor circulation, venous stasis or cold agglutinin disease. Harvard Health adds heart rhythm disorders such as atrial fibrillation to the list.
The sudden cold can put a strain on the heart and respiratory system, which could lead to complications for these individuals.
Cold water immersion may also not be suitable for those with conditions such as Raynaud’s disease, which affects blood circulation in the extremities, or conditions like peripheral neuropathy that alter sensation in the limbs.
Pregnant women should also avoid cold water immersion due to the potential for it to cause distress for both the mother and the baby.
Lastly, the elderly or those with mobility issues might find it difficult to safely enter and exit a Cold Plunge Tub.
As with any wellness practice, it’s important to consult a healthcare provider before beginning a cold plunge regimen, especially if you have any underlying health conditions or concerns.
Examples of Cold Plunge Tubs
Here are some examples of what is on the market:
- The Coldtub. A permanent tub with a built-in chiller and temperature control.
- The Plunge. A popular home tub with a built-in chiller.
- Portable ice bath tubs. These have no chiller, so you add ice to bring the temperature down. They are the cheapest way to start.
FAQ: Cold Plunge Tubs
Here are answers to some of the most frequently asked questions about cold plunge tubs.
Can You Cold Plunge In Your Bathtub?
Yes, you can cold plunge in your regular bathtub by filling it with cold water. However, the water might not reach the same low temperatures as a dedicated Cold Plunge Tub unless you add ice.
Can You Make Your Own Cold Plunge Tub?
Yes, it’s possible to create a DIY Cold Plunge Tub using a large, insulated container, like a stock tank or a chest freezer. If you convert a chest freezer, always unplug it before you get in. These options also require careful monitoring and additional work to maintain the right temperature and cleanliness.
What Ice Do You Use for a Cold Plunge?
You can use regular bagged ice from a grocery store or ice machine. You may also consider purchasing large reusable freezer packs that can be rotated in and out of the tub to maintain the cold temperature.
Final Thoughts: The Cold Recovery Bathtub
Start with warmer water and short sessions, and check with your doctor first if you have any health conditions.
Read This Next:
Sources
National Institute of Health (Research on Cold Tub Plunges)
Cleveland Clinic (cold plunge temperature and time limits)
Mayo Clinic Health System (cold plunges after workouts)
American Heart Association (cold water risks)
Harvard Health (2025 research review)
Harvard Health (cold plunges and the heart)
Reviewed October 2026. We corrected the water temperature and session length to match Cleveland Clinic and Mayo Clinic guidance, added the cold shock risk, and removed health claims the research does not support.