Are Cold Plunges Good For Your Health?
A sports medicine physician at NewYork-Presbyterian explains what we know about the health benefits and potential risks of immersing in cold water.
Cold plunges, immersing yourself into icy cold water, have risen in popularity. Scroll through social media today, and it’s not just elite athletes touting the benefits of how this form of cryotherapy has provided physical benefits.
“Over the years, cold plunges have gained a lot of traction as a lifestyle-enhancing activity because there is a better understanding of the physiologic adaptations that occur during cold immersion,” says Dr. Asad Siddiqi, sports medicine physician and chief of the Department of Rehabilitation Medicine at NewYork-Presbyterian Brooklyn Methodist Hospital.
Research shows that cold plunges may impact health, reduce inflammation, and enhance sports recovery, but more scientific studies are needed, adds Dr. Siddiqi. “There are not a lot of high-quality, large enrollment studies on cold plunges, but as more people participate in them, we are starting to get more insight into its health benefits and risks.”
Health Matters spoke with Dr. Siddiqi on what to know about cold plunges, including its benefits, risks to keep in mind, and how to do them safely.
Dr. Asad Siddiqi
What is cryotherapy?
Dr. Siddiqi: Cryotherapy refers to the application of cold temperatures to the body for therapeutic, health, and sports recovery purposes. While more people are participating in it today, cryotherapy has been around for centuries. The benefits of cold-water immersion, a type of cryotherapy ranging from cold plunges to ice bathes, have been referenced as far back as 3500 B.C.
Cold plunges involve the use of water and ice to conduct the cold temperatures faster. They can be done in several places, such as in ocean, rivers, and lakes during the wintertime, in gyms and spas or in your bathtub at home.
How can cold plunges benefit health?
Research remains far from conclusive, but so far, studies have shown that cold plunges may benefit health in several ways.
Cold stimulus makes blood vessels become narrow (vasoconstriction). When vessels decrease in size, blood flow slows, and fluid is shifted away from the arms and legs, providing relief when someone is experiencing inflammation, swelling, or muscle soreness.
We also know that cold has an impact on neurotransmitters that are important for sports performance. Cold water immersion at certain temperatures has been shown to increase the amount of circulating epinephrine, also referred to as adrenaline, in the body. This is a stimulant and an important chemical for arousal, attention, and acuity, which can translate into faster reaction times, improved reflexes, and maximal exertion. There is also some evidence to suggest that dopamine, a neurotransmitter which functions in the body’s reward system, is also enhanced by cold water immersion. Cold plunges can reduce muscle soreness after exercise, improving perceived recovery.
There also appears to be metabolic benefits. Immersing into cold water can stimulate the usage of fat as an energy source and can help with increasing metabolism.
From a chronic pain perspective, cold can also be beneficial. Similar to how we apply ice to a painful site, the idea is that cold is a stimulus that conflicts with the transmission of pain signals and helps to block them. We also know that cold temperature reduces the speed of transmission of nerve fibers, which is another way that cold can modulate pain signals that make their way to the brain.
Taking all these things in combination, we can see how this has gained a lot of traction as a good way to start the day, whether your goal is to improve overall health or enhance recovery.
Are there risks to doing cold plunges? What are signs that you should stop or avoid cold plunging?
In some situations, people experience cold shock, a life-threatening condition that occurs when the body is suddenly immersed into a cold environment without being prepared for it.
Cold shocks can significantly impact your blood pressure and heart rate. And depending on how much you’re immersing yourself; it can stimulate a very large breath or hyperventilation that can lead to drowning. If you have a very strong vasoconstriction that sends a whole lot of blood to the heart, it can increase the immediate strain on the heart, which can result in cardiac events like heart attacks. According to the National Center for Cold Water Safety, rapid and sudden immersion in water below 60 degrees Fahrenheit can result in death in less than a minute.
People who have certain medical conditions, such as Raynaud’s disease, vascular disease, neurological disorders such as multiple sclerosis or peripheral neuropathy, or significant cardiac issues, but are interested in cold water immersion should also be mindful of potential risks. They should discuss their interest in cold plunges with their medical provider to weigh the risks against the benefits.
Can you combine cold plunging with saunas or hot baths?
These can be combined with the caveat that rapid shifts in body temperature can have a range of effects on the body, and so it is recommended to avoid extremes in either direction (i.e. extremely hot saunas or extremely cold plunges) if you are going to quickly alternate between the two. A safer and more desirable approach after finishing one might be to allow the body to return to normal temperature before moving to the next.
If someone has never cold plunged before but want to try, how should they start?
If you are going to explore doing cold plunges, you should do so gradually and in a safe, controlled environment and have someone with you who can assist if necessary.
I would recommend that people ease into it and go through a period of acclimatization. For example, during a morning shower or bath, try cooler temperatures than your typical normal temperature. And then increase the time that you spend in that colder temperature.
Generally, if people want to experiment, they can start by ending their shower with 1 to 2 minutes of a cold-water blast and see how it feels.
Steps to a Cold Plunge
Dr. Siddiqi shares the steps to take to safely cold plunge.
- Prepare. Do some deep breathing and visualization, which can help you lower your heart rate and minimize the shock of entering the cold pool. This will also help make cold plunging a more pleasant and safer experience.
- Watch the clock. Start with a very short duration, like 30 seconds, to begin the process of acclimating the body. Slowly and gradually over time, you can incrementally increase the duration. In most cases, don’t plunge beyond 15 minutes due to the risk of developing hypothermia.
- Practice breathing throughout. Deep breathing beforehand can help calm and prepare you, and when immersed, controlled steady breathes can stave off the urge to hyperventilate.
- Don’t warm up too quickly after cold plunging. Gradual rewarming is typically safer and avoids rapid rushing of blood away from the heart. Your skin may feel numb after a period of time in a cold tub, and you run the risk of inadvertent tissue injury if you apply heat too quickly.
Asad Siddiqi, D.O., C.A.Q.S.M., is a sports medicine physician and chief of the Department of Rehabilitation Medicine at NewYork-Presbyterian Brooklyn Methodist Hospital. He is an assistant professor of clinical rehabilitation medicine at Weill Cornell Medicine with board certification in rehabilitation medicine and primary care sports medicine. He specializes in the comprehensive management of acute and chronic sports injuries, concussion care, and injury prevention, and he has served as a Team Physician for USA Basketball, USA Paralympic Shooting, the City College of New York, the United Nations International School, and a number of youth sport and performing arts organizations. He is an advocate for healthy lifestyles and physical activity promotion and is a firm believer that everybody is an athlete.