Posted on May 12, 2026 at 09:34 AM
No matter how much we want to convince ourselves that we can skip the ice bath (or even just the ice bucket) and sip a hot cup of coffee instead, we can’t stop hearing whispers about the potential benefits for an endurance athlete who dares to step into an ice tub.
From reducing inflammation to boosting immunity to natural mood enhancement, there has been a lot of hype (and commerce) surrounding it Cold water immersion In recent years, under different names: cold plunge, Ice bathsand cold water therapy, to name a few. But is the science there to back it up?
Cold water immersion (CWI) is a scientific term that includes techniques such as ice baths (where the water temperature is 0°C) and cold immersion (which vary in length, but are often very short). To better understand if, why, and how it’s worth convincing ourselves of these cold waters, we spoke to… Dr. Aaron Petersenassociate professor of physiology at the University of Victoria. He helped us understand the scientific consensus on CWI and offered some advice for people dipping their toes into the world of ice baths.
What science says (and doesn’t say) about cold water immersion
Starting in the early 2000s, scientific research on CWI began to flourish. However, studies have not painted a clear picture of how endurance athletes incorporate such routines into their workouts Training schedules.
Initial studies focused mostly on short-term recovery benefits of CWI after single exercise sessions rather than long-term repetition. In addition, not all studies indicate that CWI is beneficial (in fact, Some reported the opposite). Over the past few decades, more research has been done on the long-term use of CWI, which we will get to in a moment.
As it stands today, the scientific literature on CWI focuses mostly on moderately active males who train two to four times each week, Petersen says. There is not much that athletes can conclude regarding how body size and composition vary (Not to mention the hormones) may alter the effectiveness of CWI.
So it is clear that although research on CWI is not quite in its nascent stage, more studies are needed to better inform endurance athletes about the benefits of CWI and optimal techniques. Moving forward, studies will need to focus on specific demographics, such as females, as well as athletes who train every day at a high intensity and require more precise recovery techniques. In addition, factors such as frequency and timing of CWI relative to exercise should be examined in more depth.
Admittedly, the effectiveness of CWI for athletes is still somewhat mysterious, so when you try it, treat your body as a laboratory and pay close attention to what works for you (and what doesn’t).
Short-term recovery versus long-term training modifications
Petersen said that if we are talking about the short term Recovery benefits After a single exercise session, CWI appears to offer promising benefits following resistance and endurance training. In other words, you can give yourself an ice bath after a weightlifting session at the gym or after a long run, and you’ll reap the benefits…or will you?
“Short term” was the key word there. “The evidence is fairly clear that repeatedly engaging in CWI immediately after resistance training can impair natural adaptations to this training,” says Petersen. His own research This is supported, with findings suggesting that regular CWI after resistance training reduces an individual’s ability to gain strength and increase muscle size. However, after endurance training, repeated CWI appears to have a somewhat neutral effect.
But what is the definition of “recurring”? How often? Petersen said there are no answers to these questions yet. Studies on the long-term effects of CWI Participants typically perform this recovery technique after each training session. There is still no substantive evidence to show whether an athlete who uses CWI once or twice a week will benefit from physiological adaptations.
In addition, Research indicates Using CWI at different times of the day (not immediately after exercise) can alter its effectiveness, but there isn’t enough data to come up with any conclusive theories there either.
Your cold plunge protocol: temperature, time, and setting
“There is currently no clear consensus on the optimal recovery protocol for CWI, and there probably never will be,” says Petersen. This is because those very personal factors mentioned earlier – such as body size and composition, gender, age, and training styles – all influence the working definition of “optimum.”
That doesn’t mean researchers haven’t tried to find an answer from those icy waters. “To optimize recovery from endurance exercise, a water temperature of 9 to 12 degrees Celsius appears to be best when combined with immersion times of 10 to 15 minutes,” Petersen says. This is approximately 48 to 54 degrees Fahrenheit.
Petersen’s lab sets the water temperature to 10 degrees Celsius (50 degrees Fahrenheit) and keeps participants in the water for 15 minutes. As he puts it, this is “acceptable to most people.” However, some people need to start with smaller intervals, and this is nothing to be ashamed of. Who knew that sitting for 15 minutes could be considered an accomplishment of endurance?
Petersen says no special equipment is needed to practice CWI. Simply fill the bathtub with cold water and add ice if necessary to bring down the temperature (from experience, it would be wiser to buy bags of ice rather than spend all day emptying and refilling ice trays in the freezer). Of course, keep a towel and some warm clothes at the ready for when you’re ready to pull the plug.
Petersen also stressed the need to adopt a positive frame of mind. It’s beneficial not only for flattering yourself in the bathtub, but also because many studies suggest so The placebo effect of CWI is very strong. “So, if you think the CWI program will be good for you, it probably will be,” he concluded.
Safety First: The Dangers of Cold Water Immersion and How to Start Slowly
As you might expect, CWI is not without its share of risks. “Immersion in cold water causes a cold shock response and leads to rapid breathing and panting, as well as an elevated heart rate and blood pressure,” Petersen explained. It’s best for any athlete to start small — for example, by soaking only the legs, adding smaller amounts of ice, and staying for shorter periods.
After overcoming the initial shock, the average athlete may be able to recover Control their breath And synergize their minds and bodies to reap the benefits of CWI. However, those at risk Cardiovascular diseases People should consult their doctors before drowning in an ice tub.
