We are at peak cold plunge. There isn’t an influencer who hasn’t posted an icy dip clip on their feed, and every Hyrox athlete and their mother seems to be relishing in the hypothermic hype.
“There are a lot of fitness trends that are popular in the fitness world, but this is mainstream,” says Danny King, director of performance and recovery at Life Time. “You'll have random people, who barely work out, talking like, ‘Hey, You're cold plunging?’”
It’s not surprising that cold plunging has captured the attention and curiosity of the masses, with cold plunge companies and hordes of relentlessly online brands brandishing the practice’s seemingly boundless benefits, including the ability to accelerate muscle recovery, reduce inflammation, improve circulation, reduce stress, boost immunity, and generally fix your sad little life.
“Almost anything that promises that, like, you might not be as stiff or achy anymore, or you might get some positive mental health benefits—those types of things are just so on topic right now,” says King.
But after years of runaway marketing hype, the white coats are finally catching up. While the science surrounding cold plunging has long been murky and contradictory at best, a new wave of water-tight meta-analyses is revealing the science-backed, peer-reviewed facts about what cold plunging actually can—and, crucially, cannot—do for your physical and mental health.
Depending on your goals, we’re not saying that cold plunging is no longer worth your time and money. But we’re not not saying that. “There are some benefits, but not necessarily in the way that people are led to believe," says William B. Workman, MD, board-certified orthopedic surgeon at DISC Sports and Spine Center in Walnut Creek, California.
Here, leading experts break the ice on the comprehensive cold plunge research we’ve all been waiting for.
Cold plunge brands love to entice us with imagery of a muscled athlete type lowering their sculpted physique into an ice bath after a tough workout, but the science is actually pretty clear that regular cold plunging is not conducive to building muscle—especially when done right after training. Quite the opposite, actually.
In a 2024 meta-analysis published in the European Journal of Sport Science, a team of researchers parsed through the existing body of documented experiments that have investigated the relationship between cold water exposure and muscle growth. By the end of the review, they concluded that, rather than support post-workout muscle growth, cold water immersion actually hinders protein synthesis.
“The biggest finding was that cold water immersion blunts the hypertrophic response,” says Brad Schoenfeld, PhD, professor of exercise science at CUNY Lehman College in the Bronx, New York, and the study’s lead author. “Given that there were no other aspects that differed in these studies, the only conclusion you can draw is one of causality. Basically, the only differing aspect was that one group got cold water immersion and the other didn't, and the group that got cold water immersion had less growth.”
In all of these studies, cold plunging was done within minutes of completing a workout, but, according to Dr. Schoenfeld, timing may not make much of a difference. “Let's say you trained at night and [cold plunged] the next morning, or you trained in the morning and you did it in the evening or the afternoon,” he says. “Muscle protein synthesis is heightened for over 24 hours—up to 48 hours—after resistance training. So even if you did it six or eight hours later, you'd still be blunting blood flow when the muscle is looking to get nutrients to the tissue.”
“As people that are experienced doing resistance training know, it's not really the workout where the gains are made—it's in the recovery phase,” adds Dr. Workman. “You need the blood flowing in there to wash out the damaged tissue and to bring oxygen in, and cold literally blunts that."
One of the most common claims that we hear from cold plunge brands is that their products can help speed up muscle recovery. But that's not necessarily true.
In 2023, the journal Frontiers in Physiology published a meta-analysis that reviewed 20 years worth of scientific research on cold exposure and muscle recovery. The review focused on data gathered within the first 48 hours following cold water immersion. Notably, during that period, the researchers noted no reduction in blood levels of C-reactive protein or interleukin-6—two key proteins that spike during inflammation. And when subjects were tasked with performing a vertical jump test—a common measure of lower-body muscle recovery in scientific studies—after cold plunging, they actually performed worse than the control group.
“I am skeptical that [cold plunging] has important benefits on recovery,” says Dr. Schoenfeld. “One of the things we did look at was its effect on inflammatory response, which is one aspect of recovery, and it does not really impair inflammation.”
Interestingly, while cold plunging failed to move the needle on these objective metrics of post-workout recovery, it did score high on subjective measures. Subjects who cold plunged after a workout reported instantly feeling less muscle soreness and fatigue. However, these self-reported improvements proved temporary, and had worn off by the time the researchers checked in 24 and 48 hours after the initial training session. “There's a numbing, anesthetic effect of the cold, which can help,” says Dr. Workman, “but it also has a constrictive effect, which is not helpful for recovery.”
Warm water, meanwhile, actually could help accelerate muscle recovery. A 2025 study published in The Journal of Physiology found that while cold water immersion did not reduce blood markers of muscle damage following electrically induced muscle contractions, warm water exhibited a positive impact across both objective and subjective metrics, leading the researchers to conclude that warm water might be more beneficial than cold water when it comes to muscle regeneration.
One area of cold plunge research that actually does show some promise is the practice’s effect on mental health. It’s a developing field, but recent findings are slowly but surely positioning cold water immersion as a powerful tool that could be used to combat stress, anxiety, and even depression.
"Cold plunging appears to influence mental health through several interconnected processes, and one of the most immediate effects is a rapid increase in neurotransmitters and hormones that shape our emotional state,” says board-certified psychiatrist Jasmine Sawhne, MD.
A 2023 study published in the journal Biology had subjects undergo five minutes of cold water immersion, preceded and followed by neural imaging to track any potential impact on brain activity. After the cold plunge, participants reported feeling energized and inspired, among other positive emotions, and less distressed and nervous. The feedback was in line with observations from several previous studies, and MRI results showed increased activity in regions of the brain associated with emotion and self regulation.
More recently, a 2025 meta-analysis published in the journal PLoS One found cold water immersion to reduce stress levels and contribute to a greater sense of wellbeing. “This larger meta-analysis of randomized trials found that cold water immersion was associated with improvements in mood, stress, energy, and cognitive alertness across multiple studies,” says Dr. Sawhne. “While not every outcome was statistically significant, the overall pattern supports the idea that cold exposure has measurable psychological effects in healthy adults.”
But there’s a catch. “These reports often highlight the importance of consistency,” Dr. Sawhne says. And “much of the evidence is based on short-term effects.” In other words, the stress-busting benefits of cold plunging don’t hang around long after you’ve dried off. And if it’s the long-term mental health benefits you’re after, you have to cold plunge often. “This concept is called hormetic stress, which means short, manageable stresses can build a more robust and adaptable stress response system,” Dr. Sawhne says. “With time, people often report that they feel less reactive to daily pressures, and better able to regulate emotions—even when they’re not in the water.”
That’s all well and good if mental health is your top priority, or if you’re only plunging occasionally to take the edge off, but if you’re also trying to gain muscle and work out a couple of times a week, you can’t have it both ways. “You have to weigh that like a cost-benefit analysis,” says Dr. Schoenfeld. “The gains you're willing to give up, versus if you enjoy [cold plunging] and the positive effects you think it might have on other aspects of your life."
This story originally appeared in British GQ.