Read on to get the scoop on the proven benefits of ice baths and learn how you can take the plunge for the sake of your health. “The concept of hormesis is simply that if you apply a little bit of stress to a system it will get better,” Mike T. Nelson, Ph.D., founder of Extreme Human Performance, previously told mindbodygreen. Charles Tabone, N.D., a naturopathic practitioner with Pause Studio, explains that when our bodies are shocked by a drastic temperature change, our brains send a signal to the body that it’s under stress and needs to respond accordingly. When done safely (in a controlled environment for a set amount of time), immersing yourself in an ice bath can result in the following benefits: Lalitha McSorley, P.T., a physical therapist at Brentwood Physio not involved in the study, explains that the research presented in the analysis showed positive results “for muscle strength, perceived recovery, and reduced muscle soreness,” as the drop in temperature reduces creatine kinases (enzymes released when muscle cells are damaged), reducing the effects of an injury. “People are using deliberate cold exposure to reduce inflammation post-exercise and reduce inflammation generally, and people are also using cold to enhance performance in the context of strength training and endurance training,” Stanford neuroscientist Andrew Huberman, Ph.D. says on the Huberman Lab Podcast. However, as exercise physiologist Ben Greenfield explains on the mindbodygreen podcast, ideally you’ll wait at least two hours after exercising to take your plunge. This gives your body enough time to build new mitochondria2 after the stress of exercise. “Paradoxically, if you get in the cold before you work out, the sympathetic nervous system response means it can actually be a pre-workout booster,” he says. “An ideal scenario would be that you do a quick cold soak, hop in a hot tub or hot shower for a few minutes to get blood flow going, and then go hit your workout.” “A study3 published in the journal JMIR Formative Research found that cold temperatures during an immersion bath can stimulate your vagus nerve,” Laura DeCesaris, a functional medicine expert, tells mbg, adding that “stimulation of this nerve has been shown to help you relax and de-stress.” Taking regular ice baths can also activate cellular mechanisms and signaling pathways that shift the way you react to stress and make you more mentally resilient moving forward. This happens because when we dip into a cold environment (or just think about dipping into a cold environment), our bodies release “fight-or-flight” hormones like norepinephrine and epinephrine4—sometimes at levels up to five times over our baseline. By intentionally exposing ourselves to these hormones, Huberman explains on his podcast, “we can learn to maintain mental clarity and calm while we are in a state of stress, and that can be immensely useful when encountering stressors in other parts of life.” Immersing yourself in the freezing cold is also bound to give you a nice jolt of energy that you can carry with you into your day; one reason that sleep expert Michael J. Breus, Ph.D. starts every morning with a quick cold therapy session. However, “more data needs to be seen as to possible long-term metabolic impacts of cold immersion over time,” DeCesaris tells mbg. “One session here or there is likely not frequent enough to have a significant impact on body composition or metabolism.” “Since we know the hormone profile of women is changing throughout a cycle, it would be prudent, I think, for women to see how they feel trying cold water immersion early in their cycle versus later,” DeCesaris tells mbg. “Women can be more prone to higher cortisol and less resilience leading up to their period, and a cold plunge may ‘feel’ more difficult here. I’d love to see a body of research on this in the future.” David Sinclair, Ph.D., a longevity expert and Harvard geneticist, tells the mindbodygreen podcast that he suspects more research will focus on the value of getting your body out of its temperature comfort zone more generally—be it through a cold bath or a hot sauna—in the future. “Start with the commitment to get in, then with the act of calming the physiological response to the cold,” he says. “[Once you’ve jumped those hurdles], focus on the ability to maintain parasympathetic tone” (a state of relaxation) “and lastly, the willpower to remain for a few more breaths after your brain tells you to get out.” Most ice bath protocols recommend submerging your body from the neck down, in water that is approximately 50-59 degrees Fahrenheit. Your breath can be an ally as you brave the cold, and incorporating breathwork techniques like the Wim Hof method might help you out. Once your cold plunge is up, following it up with hot therapy—like a sauna or steam—can feel great and provide even more of that beneficial hormesis. There are different ways you can split this up: Huberman suggests doing deliberate cold exposure for at least 11 minutes per week in total. For best results, he recommends doing 2-4 cold sessions a week for 1-5 minutes at a time in his protocol. Or, you could aim to get in a few minutes of cold exposure daily. “I have not seen any deleterious impact from a 365 days a year [cold approach],” Greenfield says. “More is better when we’re talking about brief, consistent exposures to cold. More is not better when we’re talking about taking a 2-minute session and trying to make it a 20-minute session. Consistency trumps volume.” House of Athlete medical director Jordan Shallow, D.C., likens it to attempting to lift a weight you’re not strong enough to lift: It could cause injury. “Cold exposure is no different,” Shallow tells mbg. “It’s easy to objectify weights in a gym and have a ballpark idea of what we are capable of lifting, but most of us don’t have an established baseline for what temperatures we are capable of withstanding.” The best way for beginners to safely get started, Shallow says, is to focus on their breathing: “A good rule of thumb is exposing yourself to temperatures that don’t exceed your current capacity to go through a full inhalation and most importantly, exhalation.” Once you have a baseline, you can slowly and gradually work your way up to longer and colder baths. Use a little bit of ice during your first bath, then add more to your third bath, then a little more to your fourth bath, and so on, “decreasing the water temperature as your tolerance to the cold builds,” McSorley says. That said, even those who are cleared by a professional to practice cold water immersion need to be aware of its side effects. For example, even if you are capable of staying in the bath for long periods of time, DeCesaris warns that prolonged exposure to the cold can put you at risk for hypothermia or frostbite. Prolonged exposure can also lead to heart palpitations and other cardiovascular events,10 DeCesaris notes, as ice can “constrict the blood vessels, raise the heart rate and stress hormones.” If you start to experience any of these symptoms, it’s a sign to cut back.
