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So I’ve been meaning to write a post on Ice Baths, Cold Showers and Cold-Thermogenesis / Cryotherapy for quite some time. Several years in fact!
I believe I first came across the idea in 2010, via The Four Hour Body by Tim Ferris.
Now, let me say, I am eternally grateful to Mr Ferris for his book The Four Hour Work Week. This book truly revolutionised my life, and I continue to recommend it to everyone who’ll listen to me, and have gifted copies to countless friends.
Unfortunately however, despite his “love of self-experimentation” and science, I found critical thinking and skepticism sadly lacking in the Four Hour Body.
I did intend to do a review of the book when it came out, including the section on ice baths, but as I hadn’t yet fully implemented my own 4 Hour Work Week, I didn’t have the time.
A couple of years later, around 2012 I think, the Ice Bath fad started to get “really big” (OK, not so big that I actually knew anyone else in real life who’d heard of it or tried it, but big in t’interweb world) when Psedudoscientist extraordinaire Jack Kruse began proselytising about them within the Paleosphere.
I again intended to address it, but at this time the whole “Paleo as a Dogmatic Religion led by Peudoscientific Demagogues” started to kick off (thanks to characters such as Kruze), and the focus of the blog switched to debunking Paleo Myths, as it seemed like a more pertinent issue at the time.
Anyway, time passed, the ice bath / cold shower thing continued to float around in the fitness blogosphere, but never really seemed to gain such momentum that it warranted a post.
The Ice-Man Cometh
Fast Forward to 2016, and Ice Baths are back in the news, mostly thanks to an eccentric Dutch man called Wim Hof, aka The Iceman…
The Iceman started to hit the headlines several years ago, with his incredible feats of cold endurance – Climbing Everest in nothing more than a pair of shorts, swimming unprecedented distances under polar ice, breaking world records for staying submerged in ice water and so forth.
All great stuff, I truly believe the world is enriched by outliers such as Mr Hof, it’s a fantastic thing that as a species, we keep trying to do new, crazy things, just for fun or for a challenge, purely to test our limits and boundaries, and not to prove anything or win anything.
Anyway, the Iceman was initially a fun, harmless, sideshow attraction, until (IMHO) that is, he launched “The Wim Hof Method”.
The Wim Hof Method (WHM), you see, combines breathing exercises, meditation and extreme cold exposure, and promises to:
Besides helping you learn how to control your autonomic nervous system, Wim’s method has the following benefits:
Positive influence on the immune system
Positive influence on your mind and body
Improvement of blood circulation
Improvement of concentration and focus
Greater self-confidence and conscious development
What’s more, the WHM is “Proven By Science”. Oh yes. There’s even a direct link to the full text pdf on the website:
Based on the fact that this ice bath / cold shower / Cold-Thermogenesis / Cryotherapy or whatever the heck you want to call it doesn’t seem to be going away, I thought I’d better finally pull my finger out and write something about it.
Also, although in the grand scheme of things, I think ice baths are still, and are always going to be, pretty niche, I hope this article can also serve as an example of how science can be abused, misinterpreted, or just badly done, and also the importance of separating efficacy from effectiveness.
So before deciding whether or not you should plunge yourself into a freezing cold bath of ice water, or hand over huge wads of cash for the fancier sounding cryotherapy version, you first need to ask yourself exactly what you are expecting to gain from the experience.
There are 3 main purported benefits for putting yourself on ice:
- Enhanced Recovery Post Exercise,
- Increased Fat Burning/expedited Fat Loss
- Improved Immune Function
The latter is the claim from the Wim Hof method, which is allegedly proven by the aforementioned 2014 study, so I’m going to start here, and have a look at just how robust the science actually is.
Icing for the Immune System: A Lesson in How Not to do Science
So what does the WHM study tell us about the benefits of cold exposure for the immune system, or anything else for that matter?
A big fat nothing!
This is a randomised study, with a control group. The gold standard, no? So why am I not convinced by the results?
- Three different interventions are tested at the same time
- No Placebo for the Control Group
- Three control participants rejected?
- Over Interpretation of Benefits
- Cold Therapy Reduces Exercise Induced inflammation Leading to Improved Performance in the Following Session
- Cold Therapy Reduces Exercise Induced inflammation Leading to Reduced Adaptation to Training, and therefore Slower/Reduced Long-Term Performance Gains
The authors do acknowledge this at the end of the study (though of course this doesn’t help the vast majority who read only the abstract). With a study such as this, there is absolutely no way to know which, if any, of the interventions had an effect.
Yes, it’s possible that there is some kind of synergistic effect between the 3 interventions, but it’s also possible that any or all effects come from just one, or even that the interventions interfere with each other, and the combination of the 3 is less effective than just 1 or 2 alone.
To effectively test the WHM to see which aspects of it actually have an effect (if any), it would be necessary to have at least 4 intervention groups – 1 for each independent arm, and 1 for the 3 combined.
Of course, this is going to significantly increase the cost of the study, as it will require at least 2.5 x the number of participants.
I would have thought at the very least, however, they could have had 2 intervention groups – Meditation and Breathing (not an unusual combination) and Cold Exposure. The cold exposure, is after all, the less practical, more out there, and less pleasant aspect of the method.
Equally, if not more significant, is the fact that the control group is not given any kind of placebo intervention.
This is the number 1 S.C.A.M (Supplements and Complementary/Alternative Medicine) classic for creating “evidence” for the efficacy of your intervention.
If a study has no placebo control, you have no way of knowing if the effects of the intervention are anything more than placebo. Duh!
Three members of the control group were rejected as their immune responses were considered abnormally low. This was assumed to be an issue with the endotoxin injection (all 3 received from the same ampoule).
The low immune responses from the intervention group however, were all assumed to be due to the WHM.
One would have thought the researchers could have checked with the manufacturer for issues with the ampoule lot number, but this didn’t seem to interest them. Rather they were happy to reject results that didn’t fit with their agenda.
An example of why testing should always be blinded!
So let’s give Hof and the researchers the benefit of the doubt, and say that the results were a genuine result of the intervention, not just random chance or placebo effect, what then? What does this reduced immune response mean, is it something we should be getting excited about?
The “startling” results of the study were that:
In the intervention group, plasma levels of the anti-inflammatory cytokine IL-10 increased more rapidly after endotoxin administration, correlated strongly with preceding epinephrine levels, and were higher. Levels of proinflammatory mediators TNF-α, IL-6, and IL-8 were lower in the intervention group and correlated negatively with IL-10 levels.
Basically, the immediate inflammatory immune response to the injected endotoxin was significantly lower in the intervention group than the control group (well, once 25% of the control group had been eliminated due to low responses, but I digress).
An interesting result from a scientific standpoint, but fairly meaningless in real world terms.
Has the WHM been shown to prevent or cure any kind of illness? No. Is this attenuation of the immune response proven be a good thing? No.
Icing for the Immune System Summary
So, just to recap, if you were thinking of trying Ice Baths in order to boost your immune system, either as part of the Wim Hof Method or otherwise, don’t bother!
If the WHM does have any effect on the immune system at all, it is most likely that these effects come from the breathing techniques, and it is very unclear whether these purported effects would actually have any real life benefits – they could even turn out to be negative!
Icing for Enhanced Recovery and Improved Performance
Ice baths and/or the fancier and more expensive version of Cryotherapy, have been popular with athletes for many years, with some very high-profile advocates including Andy Murray, Mo Farrah and Floyd Mayweather.
We’ve seen before, however, that just because a successful athlete claims something works, doesn’t mean it does.
So if we ignore the celebrity endorsements, what does the science actually say? Does plunging yourself in a freezing cold bath of ice after your gruelling training session help you recover faster, and ultimately perform better?
The answer… Yes! Wait, no! Er, maybe?
There’s been a fair bit of research conducted on ice baths for athletic performance. Though it is highly unpleasant, it’s relatively cheap and easy to implement, so easy to study, and easy for real world athletes to incorporate into their routine.
Surprise surprise, despite their popularity, there is little compelling science to back up the claims that ice baths are a wonder tool for enhancing recovery and performance.
The results, and theories behind the mechanisms behind ice baths, are somewhat conflicting and contradictory, but most of this conflict can be attributed to the fact that there are really two potential applications – recovery AND/OR performance enhancement.
Improved Recovery doesn’t Necessarily Equal Improved (Long-Term) Performance
There are two (kind of) conflicting theories behind ice baths or cryotherapy treatments post exercise, though as we’ll see, they are really two sides of the same coin.
Proponents of Ice Baths post exertion posit that the reduced inflammation enables the athlete to perform at higher levels in their next session.
It sounds plausible, and there are lots of people who swear by its benefits, but I personally haven’t found much evidence to support the claim.
Halson et al found some very small, but inconsistent, performance improvements in their 2014 study, but they were so small that the best they could conclude was that:
Although some effects of CWI on performance were unclear, data from this study do not support recent speculation that CWI is detrimental to performance after increased training load in competitive cyclists.2
Similar results were found by Stanley et al in two studies3,4, again with cyclists. Despite cyclists reporting they felt more recovered after the ice baths, performance improvements were either barely significant, or non existent.
The only study I came across which appeared to show a significant benefit to ice baths for improved performance, thanks to enhanced recovery, was a study into endurance running to exhaustion conducted by Dunne et al5. She had her subjects do consecutive runs to exhaustion, separated by 15 minute breaks. These breaks were either simply resting, or in a cold bath, or an ice bath. The athletes that took the baths performed significantly better than those that didn’t, with the ice bathers out performing the cold water bathers.
The evidence for using ice baths for recovery, it seems, is very limited, any performance gains will be likely be only very slight, and only if the bouts of exercise are extreme and very close together – i.e. daily or multiple bouts in the same day.
One must also consider that any performance improvements could well be down to placebo effect. It’s well-known performance can be influenced massively by belief. An ice bath is surely a very powerful active placebo. If you believe you are better recovered, could this not account for the very marginal gains? As with the WHM study, some kind of sham recovery control group, or alternative genuine method would have been a better control.
I said earlier that the arguments of the pro ice vs no ice advocates were conflicting – but this isn’t exactly true, as both sides do agree that cold water therapy / cryotherapy / ice baths etc reduce the inflammation after a hard bought of exercise.
The differences arise in opinions as to whether or not this is a good thing.
The pro side argue that this reduced inflammation leads to improved performance in the next workout – more reps, faster times, longer duration etc, which in turn should lead to better long-term performance also.
The counter argument, however, is that this post workout inflammation is actually a necessary part of the body’s recovery and adaptation process. By suppressing this mechanism, you hinder the body’s ability to recover and adapt, and thus potential performance gains are reduced.
This theory appears to be supported by the evidence, at least as far as resistance training is concerned. For example studies by Yamane et al6 and Roberts et al>a href=”7″>7, which found that subjects who used cryotherapy post workout for recovery, made lesser gains in max strength and strength endurance than subjects who performed active recovery on an exercise bike.
Icing for Athletic Performance Summary
Despite its ubiquity, and notable celebrity endorsements, there is actually little evidence for the efficacy of ice baths or cryotherapy for the enhancement of athletic performance.
On the contrary, based on the available evidence, it would seem best to AVOID regular cold water immersion post training session, as it may actually compromise your body’s ability to adapt to the training stress and hinder your performance gains!
Inflammation has become the bogey man of health and performance – anything that is pro-inflammatory is bad, anti-inlammatory is good – but this is an oversimplification/misunderstanding. Yes, chronic inflammation is bad, but in a healthy, well-balanced body, some well placed inflammation is likely a natural part of the body’s maintenance and repair program. Quashing all inflammation is likely overkill with negative consequences.
The exception to this rule of avoidance, could be during periods of intense, frequent competition.
If you’re competing in the Tour de France, or Wimbledon, or some other intensely gruelling multi-day competition where short-term marginal gains in performance could make or break your success, jumping in a bath full of ice is probably worth the risk and discomfort (if winning is everything for you…).
For mere mortals however, it’s probably not really going to make any difference.
Ice baths for Fat-Loss
OK, so far, the ice baths aren’t doing so well. No evidence that they are going to boost your immune system, nor help your athletic performance. But how about helping you shift some of that blubber from your midriff though? I mean, it makes sense, seals and walruses spend no end of time in ice water and look how slim they are…
Hey, I’m being flippant of course. Just because spending all day in freezing conditions doesn’t make pinnipeds skinny, doesn’t mean it can’t work for humans, we have very different genetics after all.
The idea of icing / cryotherapy for fat loss was popularised by Tim Ferris, in his second book The Four Hour Body.
Apparently, he was alerted to the potential benefits of cold therapy for fat loss by an ex NASA scientist, Ray Cronsie. (NASA Scientist… must be good stuff…).
Ray came up with the idea of using cold water immersion to help speed fat loss, after hearing that Michael Phelps ate 12000 calories per day. Ray figured that Phelps’s training alone couldn’t account for this huge calorie consumption, but perhaps the additional conduction of heat away from the body from spending so much time in cold water could (or perhaps the figure was simply made up to gain media attention…).
So Ray started a chilling new fat loss regime… He would drink a gallon of ice water every morning, sleep without covers, go for walks in the snow wearing just a t-shirt. He was impressed by the results – he lost more fat in the frist 6 weeks of his icy experiment, than he had in the previous 12 weeks of diet and exercise alone.
Ferris heard of Ray’s experience, was intrigued, and decided to research and experiment himself.
Fair do’s to Ferris for being quick to spot that the numbers didn’t exactly add up.
Experiments have indeed shown that cold water immersion can increase calorie burning8 by up to a whopping 400%, wow! Ah but wait, hang on, we’ve been fooled by this cunning % shifts before… In real terms however, this only translates to a maximum of an extra 15.5g of fat. To shift a kilo of fat, therefore, you’d be looking at sitting in an ice bath for around 130 hours! Hmm.
Undeterred however, inspired by Ray’s fantabulous results, Ferris hypothesised that while the extra calories burned while actually undergoing the cryotherapy couldn’t explain the fat loss, perhaps the cold exposure was prompting the body to produce more BAT – Brown Adipose Tissue – a metabolically active type of fat, which is stimulated to burn fat to produce heat. Perhaps frequent cold exposure, could stimulate the body to grow more brown fat, and thus become more efficient at burning fat?
Ferris went onto conduct his own self experiments, using 20 minute ice baths or ice packs placed on the back of the neck and shoulders (both in combo with the fat burning stack of ECA – ephedrine and caffeine). He apparently found them both effective, the ice packs only around 60% as effective as the baths, but “less torturous”.
So there we have it – ice baths are great for fat loss – conclusively proven by Tim Ferris and a NASA scientist no less!
Oh, but hang on, if you’ve read my previous article “The Pros and Cons of Self-Experimentation” you’ll be right to question the confidence of these conclusions.
Now, in defense of Ferris – he does appear to have conducted his self experimentation pretty well, testing one protocol, changing for another etc.
No matter how well you conduct experiments on yourself though, you’ve always got to factor in the placebo effect as a possible explanation for positive results – for this reason it is necessary to look at your results in the context of larger, rigorous studies, in an attempt to judge whether any perceived results are likely to be actual effects of the intervention or simply an illusion.
When I came to have a look for the pertinent research on the topic, I came across this nice little review here by Muscle Evo: Cold Showers for Weight Loss: Do They Work? Rather than try to reinvent the wheel, I’m going to let you read Mr Finn’s take on the matter, which I’d largely concur.
In summary, cold exposure can indeed stimulate brown fat, and increase calorie burning, but probably only by a very teeny tiny amount.
Taking Ice Baths are like using the Elliptical Machine
To me, when it comes to fat loss, ice baths are a bit like exercise. Not worth the time, effort and discomfort! (At least under my definition of exercise).
NB – If you’re not familiar with the above article, I’m not suggesting a sedentary lifestyle. On the contrary, the more active we are the better doing fun, interesting, challenging or practical activities. It is just dull, monotonous “exercise” such as plodding away on the elliptical machine or a stationary bike with the sole aim of burning calories which should be avoided!
Take the two following questions:
- Can cryotherapy or extreme cold exposure increase your metabolism and the amount of fat your body burns?
- Should cryotherapy or extreme cold exposure be part of a sensible fat loss strategy?
At face value, very similar questions, though personally, I’d have a very different answer to each.
- Yes – Both exercise and cold exposure can increase the number of calories and fat your body burns, but…
- NO, IMHO they shouldn’t be part of a sensible fat loss routine!
Why? Because they are completely unnecessary, and potentially counter productive!
As far as most people are concerned, exercise is not an effective means of aiding weight loss. Though your body burns extra calories, appetite also tends to increase, thus no deficit is created, and no fat is lost. Many people even over compensate, rewarding themselves for their hard work and dedication with calorific treats, ultimately gaining weight.
Cold water immersion has also been shown to increase appetite:
In summary, a short period of post exercise water immersion significantly increases ad libitum energy intake in the subsequent meal among young, trained men. This may be attributed, in part, to a tendency for lower levels of circulating leptin, together with higher active ghrelin after immersion in cold and neutral water, respectively.8
So while freezing your nuts off might very slightly increase the amount of fat your body is going to burn, it’s also going to make you hungrier. Cold and hungry – what fun!
Of course, exercise does prove an effective fat loss aid for some people. For these personality types, committing to an exercise routine, also helps them commit to sticking to an eating plan. They are less likely to call into a burger joint or cake shop on the way home from the gym, than they might have been had they just gone straight home from work. “I’m not going to undo all that hard work I’ve just done” mentality.
I’d think that perhaps, ice baths and the like, may have similar psychological effects for those willing to partake in them, such as Ferris and Cronsie. If you’ve committed to regularly sitting in a bath of ice, or otherwise exposing yourself to unpleasant extremes of temperature, I’m willing to bet you’re going to double down on your healthy eating plan.
Pure speculation, but while there are evidently many who will call into the donut store after a 30 minute plod on the cross trainer watching reality TV, I think there are few people who would do so after exposing themselves to the torture of 20 mins of icy hell.
My best guess, is that the large increases in fat loss experienced by Ferris and Cronsie during their cold therapy self experimentation, was more likely down to psychological factors, than to any physiological changes to metabolism.
When it comes to losing fat, understanding your own psychology is definitely key. Everyone is different, and for this reason, there is no 1 perfect diet, training routine, or fat loss secret.
On paper, fat loss is as simple as burning more calories than you consume. In practice, however, it’s rarely that simple.
While some might argue that beasting yourself in some kind of insane workout, or freezing your jingle bells off in a cryochamber are good for mental toughness, and will reinforce your discipline and will power, I’d be inclined to disagree.
Using a food diary and keeping your kitchen cupboards free from junk would IMHO be more practical and effective techniques, amongst many more.
Don’t Mistake Comfort for Happiness – Dean Karnazes
Now please, please, don’t misinterpret what I have said above as an excuse to stay at home, sat on the sofa with the central heating turned up to full!
I don’t like cold showers, or ice baths.
Call me a “friolero” (handy Spanish name for people who don’t like the cold) if you like, but regularly exposing myself to either of these two forms of torture is not my idea of fun, so why on earth would I do it when one can achieve the same goal (low body fat) simply through good eating habits and an active lifestyle.
All that said, however, I’m not averse to cold exposure. Wild swimming in icy lakes, hiking and camping in snow-capped mountains, continuing outdoor training all year-long – these are all things I do, despite my “friolero” tendencies.
If I’ve burned extra calories than I would have done had I swum in a heated pool, found a mountain in a warmer climate, or trained in a temperature controlled gym, great, but this wasn’t the primary motivation behind any of them.
In short, if you are considering taking cold showers, ice baths, or worse yet, stumping up huge wads of cash for fancy shmancy cryotherapy, in the hopes of achieving some effect – be it enhanced immune system, improved athletic performance, or more rapid fat loss, don’t!
If, on the other hand, you want to go for a new year’s day swim in sub-zero conditions, just because, well why the hell not, more power to you, maybe I’ll see you there!
This post was written by Simon Whyatt and first appeared on www.livenowthrivelater.co.uk
This article was written by Simon Whyatt and first appeared on the blog Live Now Thrive Later.
2 Does hydrotherapy help or hinder adaptation to training in competitive cyclists?
Halson SL1, Bartram J, West N, Stephens J, Argus CK, Driller MW, Sargent C, Lastella M, Hopkins WG, Martin DT
3 Consecutive days of cold water immersion: effects on cycling performance and heart rate variability.
Stanley J1, Peake JM, Buchheit M.
4 The effect of post-exercise hydrotherapy on subsequent exercise performance and heart rate variability.
Stanley J1, Buchheit M, Peake JM.
6 (PDF download) Post-exercise leg and forearm flexor muscle cooling in humans attenuates endurance and resistance training effects on muscle performance and on circulatory adaptation
Motoi Yamane, Hiroyasu Teruya, Masataka Nakano, Ryuji Ogai, Norikazu Ohnishi, Mitsuo Kosaka
7 Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training.
Roberts J, Raastad T, Markworth JF, Figueiredo VC, Egner IM, Shield A, Cameron-Smith D, Coombes JS, Peake JM
8 Postexercise water immersion increases short-term food intake in trained men.
Halse RE1, Wallman KE, Guelfi KJ.