What is cold therapy?
Technically “cryotherapy” or “cold therapy” refers to any type of cold exposure which has health benefits. The health benefits of cold therapy vary from what you know already (it helps after an injury) to what you don’t know (it can lower your blood sugar). Many of the benefits of cold therapy have been known for decades. However, what has captured our imagination is whole body cryotherapy (WBC).
We see Tony Robbins hauling around his cryo tank and we see NFL players in tanks, smiling widely and touting the sports performance benefits.
“Cryo centers” claim that their cooling machines can boost metabolism, increase endurance, improve sleep and even help you feel younger and happier.
How much of this is hype and how much is real?
How much is due to the WBC procedure of seriously cold exposure and what can we expect from things like using ice packs or taking an ice bath? What about the benefits of cold showers?
First, let’s look at what’s what and then what’s been studied to get some answers on whether or not you should shell out as much as $250/session for whole body cryotherapy (WBC).
WBC involves a brief exposure to extreme cold via a cryochamber – a human-sized tank which is then filled with liquid nitrogen-cooled air. A session is typically 2-3 minutes in temperatures that are seriously cold at -130°C (-266°F).
However, as I’ll discuss we now know from many comparison studies that we get the same effects from 20° C (68° F) 5 min showers, 10-30 minute ice packs, 10-60 minute (brrrr!) ice baths in temperatures between 55°F-66°F, and ice swimming (times and temps not listed in studies but again- brrrrr) for many of the pathways I’ll be discussing in this article. Also not studied- ice vests and ice caps. And the practice of dunking one’s face in ice water hasn’t been studied, either. At the end I’ll give you my take on what will work, what’s feasible and what’s likely not.
Perhaps the best health benefits of cold therapy involve lowering the inflammatory response
One of the ways we can test for inflammation is to monitor what are called inflammatory cytokines such as IL-6. The cytokine response after thermal stress (sauna + subsequent swimming in ice-cold water) was investigated in subjectively healthy persons. Two groups were studied at the end of the winter season: experienced (“habitual”) and inexperienced winter swimmers. Blood was collected first; at rest, then after a sauna bath and finally; after a short swim in ice-cold water. In this particular study there was a definite reduction of the IL-6 class of inflammatory cytokines in the swimmer group.
In other studies using different types of cold stress, the cytokine associated with cancer and auto-immune disease called TNF-alpha was decreased. Yet other studies with varied modalities showed an increase in the anti-inflammatory hormone; adiponectin. We’ll get back to adiponectin which is much more than an inflammatory “marker” when we discuss weight loss. Right now, let’s continue examining inflammation; but at a local level; where all the hoopla started.
Post-exercise muscle repair
For years, athletes and coaches have wanted to know how best to use cold therapy to augment post exercise muscle repair. The “routine” used to be that cold therapy of any kind (including when WBC was first introduced) was done right after a workout ended. However recent studies reveal that if you do cold therapy immediately after exercise, you interrupt your body’s healing pro-inflammatory response (yes, you read that right).
Doing so may actually reduce the benefits from exercise and inhibit recovery and subsequent performance. Imagine that? Here’s what you do to maximize relief for sore muscles. Instead of icing right away, wait an hour post-exercise to use local icepacks, ice baths or WBC to improve performance and recovery. In one study, WBC performed within a whopping 48 hours of an elite race (but comparatively; not within an hour of the race) improved the athletes’ recovery. But what about the bulk of the literature?
A systematic review of 9 clinical studies looking at relief from cold water immersion (now accepted as “as good as” WBC) is as follows. The available evidence suggests that CWI is “slightly better” than passive recovery for muscle soreness. The results also demonstrated the presence of a dose-response relationship. Analysis of all the times and temperatures revealed that CWI with a water temperature of between 11 and 15 °C (51.8-59° F) and an immersion time of 11-15 min provided the best results. This review did not look at other metabolic parameters such as those I’m going to discuss next. Remember inflammation and how cold therapy lowers adiponectin? Well, let’s start there when we discuss the weight loss potential of CWT (cold water therapy).
Several studies have demonstrated that CWT increases adiponectin levels. However, the data is too scattered regarding methodology and possible coupling with exercise to make definitive conclusions. However increased adiponectin levels are associated with a decrease in the incidence of obesity, diabetes, and even auto-immune diseases (that; via suppression of TNF-alpha). So – just keep CWT via adiponectin as a “maybe” in your CWT arsenal for now. Then there’s more definitive weight loss information regarding brown fat.
Humans have stores of active (BAT); brown fat tissue . Unlike white fat, which stores energy and is made up of simply “body fat”, brown fat actually uses energy by burning calories. BAT can actually turn calories from food into heat. It generates heat by uncoupling proteins within the mitochondria. Yes-we’ll get to mitochondria soon. Let’s look at what kind of BAT activity we see with CWT. Do note that a lack of BAT has been successfully linked to obesity.
Studies do indeed show that cold exposure increases BAT activity which then leads to increased calorie burning. Researchers have even concluded that frequent cold exposures might be an good way to address the current obesity epidemic.
All of the BAT studies have been done with ambient air studies. Cold exposure increases shivering which is an obvious but uncomfortable way to burn calories. However it also induces (at obviously higher temperatures); non-shivering thermogenesis. Non-shivering thermogenesis might occur with temperatures as high as in the mid-60’s (Fahrenheit).
Recall the discussion about inflammatory cytokines; above? Studies have shown that several inflammatory cytokines including TNF-alpha and IL-6 (and other IL cytokines) increase pain. In a recent study, levels of IL-6, IL-17A and IL-1β gene expression levels were quite significantly down-regulated with the use of simple cold packs. This is an illustration of something that just plain “makes sense”, right? But there’s more!
Cold compresses have been scientifically compared to WBC as well as to ice baths to ease the pain of rheumatoid arthritis. No difference was found in subjective pain scales between all three modalities.
Another anti-inflammatory response from cold therapy is the measurable release of the neurotransmitter; nor-epinephrine. Studies have demonstrated that the short term pain relief from nor-epinephrine makes intensive physical therapy more tolerable for chronic pain. This has been demonstrated in patients who have chronic low back pain, fibromyalgia, and osteoarthritis.
Finally, studies show that cold therapy also elevates endorphins; your natural pain-reliever. When your body experiences pain or stress, endorphins are released by the brain’s pituitary gland, spinal cord and other parts of the nervous system to make you feel better. Cold is “thermal stress” which is exactly how it works.
As you have read, exposure to cold temperatures can increase levels of adiponectin. One study found that adiponectin levels increase by 70% after 2 hours of systemic cold exposure. While definitive studies relating cold to weight loss haven’t been performed, studies looking at blood sugar have.
In rat studies, cold exposure increases glucose uptake in the peripheral tissues – (by enhancing glucose oxidation via insulin-independent pathways). Cold exposure can enhance the body’s response to insulin, allowing glucose to be cleared from the blood quicker.
And then there is the SIRT1 pathway; the important enzyme for glucose regulation, regulation of body fat, and cholesterol; even blood pressure. Many environmental (air temperature manipulation) studies show that SIRT1 is augmented with cold exposure.
My personal favorite of all the benefits of cold therapy: Mitochondrial biogenesis
Learn to love your mitochondria. In the article where I gave you all sorts of fun ways to help your mitochondria, I gave you all the reasons why. Here’s a little review. Mitochondria produce adenosine triphosphate (ATP) which your body then uses as energy; or fuel. Some cells have more mitochondria than others; namely your brain, heart and muscles.
The creation of new mitochondria and destruction of worn-out mitochondria are both necessary for optimal and vibrant aging. It’s needed to keep your energy levels at their peak. It’s needed for many key biochemical processes. Conversely, mitochondrial dysfunction puts your energy levels at rock-bottom and contributes to numerous physical problems.
Mitochondrial dysfunction is a characteristic of aging, and nearly all diseases. Neuro-degenerative diseases such as Alzheimer’s disease and Parkinson’s disease are essentially “mitochondrial disorders.” Obesity, metabolic syndrome, diabetes and heart disease are all associated with mitochondrial dysfunction.
What about auto-immune diseases such as Crohn’s disease and Rheumatoid arthritis? Yes, indeed. Even some psychiatric conditions have a mitochondrial component. Naturally, fatiguing illnesses, such as CIRS (mycotoxin-biotoxin innate immune disorders), Fibromyalgia, Chronic fatigue syndrome, and Gulf War Syndrome have prominent mitochondrial near-failure. Lastly, chronic infections and cancer involve mitochondria as well. So now that you know you want great mitochondrial function, let’s explore the role of CWT.
When we think of failing mitochondria we always have some component of fatigue. This couldn’t be better examined than taking a look at patients with Chronic Fatigue Syndrome. This is best illustrated by looking at a study involving chronic fatigue patients. Twice daily 5 minute 20° C (68° F) showers improved symptoms of fatigue.
While the researchers didn’t discuss mitochondrial bio-genesis in this particular study, others certainly have discussed the benefits of cold showers for your mitochondria.
Studies in mice using immersion to just above the shoulders in 20° C (68° F) water and then looking at both fatty (adipose) tissues and lower leg tissue post exercise and post cold immersion show a definite uptick in both fatty tissue and muscle tissue in formation of new mitochondria.
And then there is the SIRT1-mitochondrial connection. The substance which “gets the genetic ball rolling” in mitochondria; peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) has been implicated (in numerous studies) in mitochondrial biogenesis; the formation of new mitochondria. The enzyme SIRT1 performs the initial biochemical steps to activate PGC-1α. This has been studied at length looking at the role of intermittent fasting, caloric restriction and improved longevity; with this detected as an important underlying biochemical mechanism.
If we extrapolate that data, we might make the leap that SIRT1 activation from cold exposure will improve longevity. Some researchers have made that leap. I’ll let you decide.
Cold therapy lowers cortisol levels when it is done on a continual basis. Now, we know that one of the causative factors for leaky gut is a chronically high cortisol level. So, bringing down your cortisol will not only help your gut lining stay intact, it will enhance the 70% of your immune system which resides in your gut.
In addition, studies show that anti-tumor white blood cell activity is probably enhanced after cold therapy.
Enhancement of detoxification pathways
One clinical study found that people who swim in ice cold water on a regular basis had high levels of the intra-cellular anti-oxidant, glutathione. The reduced form of this powerful antioxidant is crucial for the detoxification process.
In one study which looked at athletes given WBC (with no comparison to ice packs or water immersion) enhanced superoxide dismutase; an enzyme which allows the body to deal with free radicals more efficiently.
A landmark study demonstrated that cold water immersion (CWI) at 57°F (14°C)- also known as an ice bath; for 1 hour increased the happy (and pain-reducing) brain chemical; nor-epinephrine by a whopping 530%. Another feely-good brain chemical; dopamine, increased by 250%. Researchers postulated that you could get similar results from whole-body cryotherapy sessions at -250°F 2-3 times a week. Other researchers took this data and proposed an as-yet-not-done experiment. Here’s what they proposed, taking studies of nor-epinephrine and endorphins into consideration:
The hypothesis is that cold showers (20° C (68° F) , for 2-3 minutes, preceded by a 5-minute gradual adaptation to make the procedure less shocking) performed once or twice daily would help depression. The proposed duration of treatment would be several weeks to several months. The following evidence was added to the above to support the hypothesis. Exposure to cold activates the sympathetic nervous system which then increases the blood level of beta-endorphins and nor-epinephrine.
The scientists wrote that “additionally, due to the high density of cold receptors in the skin, a cold shower is expected to send an overwhelming amount of electrical impulses from peripheral nerve endings to the brain, which could result in an anti-depressive effect.” I don’t know what they meant by this-perhaps they were likening a cold shower to low-level ECT (electro-convulsive therapy)?
Collagen production has been measured to increase after WBC. In addition, the activity of collagenase (the enzyme which breaks down collagen) slows down. We know that cortisol levels decrease with cold therapy, and cortisol does it’s best to cause collagen breakdown and sleep disruption. Speaking of sleep, we have evidence that cold helps that, too.
A Dutch study found that by cooling core body temperatures just slightly by cooling the bedrooms down to 68 degrees F; participants doubled their time in restorative, slow wave sleep. The mechanism of action is thought to be due to the role of nor-epinephrine in levels of sleep.
Bottom line : Do Cold Therapy at Home
My take on all of this: Please don’t immerse me in an ice bath full of cold water at 57°F for an hour unless you are going to give me a winning lottery ticket at the end of the ice bath. Yes, by all means, let’s use cold to increase endorphins, reduce inflammation by inhibiting inflammatory cytokines and raising adiponectin. Let’s enhance SIRT1 and mitochondrial biogenesis. Let’s ease pain, raise neurotransmitters to feel happier, and have a positive impact on metabolic pathways to lose weight and decrease blood sugar levels. Make everyone feel more energetic? I’m in. Let’s recover optimally from strenuous exercise. So how do we accomplish this?
We know that WBC appears to be pretty consistently equal to ice swims or ice baths. WBC, however is not readily available to everyone and tends to be pricey: $125-$250 per session. Ouch. Almost as painful as that one hour ice bath. It seems to me that we can accomplish similar results with three methods I’ll describe that a collection of patients and friends are using; with positive feedback from all groups.
Method #1: Take a hot shower twice daily and at the end; turn it as cold as it will go for 30 seconds, letting the water beat down on the back of your neck, your chest and your muscles (where the mitochondria are the most dense). This group reports more energy and improved cognition.
Method #2: Get into a “decently cold” shower (going for the 68 degrees study) for 5 minutes, 2x/daily. Oddly enough, this is more “difficult” than the 30 second “cold blast” with reports of similar results. A couple of patients also have found lower blood sugars and vastly improved weight loss – but (alas)-this is not a controlled study and they have also recently embraced my mitochondria-friendly, weight loss-friendly nutritional ketosis diet.
Method #3: Get a 10×6 inch gel-cold-pack and an ace wrap. Place the cold gel pack between your shoulder blades and ace wrap it in place, around your back and chest. Use it while seated or lying on your back. This group reports pain relief and improvement in energy when they do this for 20 minutes 2x/day. I asked this group to also put a cold pack on either the back of their neck or their forehead but after trying it myself, I understood why they couldn’t do this for more than 3-4 minutes. I asked three biotoxin (mold) patients about their level of happiness and all had greatly improved. However I can’t separate out the role of pain reduction and detoxification. Not to mention integrative supplements which augment the “happy neurotransmitters.”
If you wanted to get super scientific about this, you’d get a thermometer and do the ice baths or you’d do the WBC. I see ice vests for sale, but putting cold packs on one’s chest feels super-cold to me. Perhaps one of those vests with ice only in the back would “do the trick.” I also see ice “helmets” for sale. I’ll “bite” that these will stimulate brain mitochondria and might just improve cognition. I would suggest that you try putting a cold pack on your head before investing in a cap. My last thought is that swimming in a non-heated pool is a nice “thermal shock” and just might mimic the results of ice-swimming.
This subject truly interests me so I’d love to hear what you have tried and what you think.