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Staying Cool with MS

ActiveMSers is the world’s leading resource for reviewing and testing cooling vests. After testing over 20 models, this exclusive guide details the science behind how cooling vests help combat overheating with multiple sclerosis (known at Uhthoff’s phenomenon), what to look for when purchasing one, the best types of vests for your particular situation and needs, and the top performers.


With summer inconveniently rearing its ugly head annually, us folks with multiple sclerosis cringe with anticipation. Like breakfast cereal and gravy, warm days and MS just do not mix. We need to stay cool to prevent our bodies from getting angry and plunging us into a seemingly endless malaise along with a list of symptoms that could rival an eight-year-old’s list of wanted presents from Santa.

Why does this happen? The most common hypothesis: the more heat, the more your body’s nerve impulses can escape due to demyelination. Current is moving too fast and the signals become muddied, meaning a rise in MS symptoms. Cooling increases conductivity, prolonging the current available, meaning more current can flow through your nerves and signals are more reliable.

To avoid the heat of summer, one option is to stay indoors and bask in the chilly pleasures of air conditioning. But we are ActiveMSers, desperately seeking pleasure without walls. Now ideally we’d just wear a little bracelet air-conditioning that regulates cooling, but while such things have been invented, their effectiveness when it comes to medical conditions is suspect, and that may be putting things generously. That said, we do have cooling vests—as well as innovative cooling systems—at our disposal. Why do they work and why does it matter?

All 20+ cooling vests reviewed (from manufacturers including Polar Products, Steele, ArcticHeat, Maranda, TechNiche International, Glacier Tek, First Line Technology, Thermapparel, and others) were donated for testing purposes. Members of ActiveMSers can save up to 20% on select cooling vests with reserved coupon codes. To get your discount, join ActiveMSers today. NOTE:  As an Amazon Associate I earn from qualifying purchases. These funds help maintain this website. Details.


Scientists have been investigating the power of cooling in multiple sclerosis for decades. Indeed, in 1977, researchers subjected patients with multiple sclerosis to moderate hypothermia, which resulted in a “striking improvement” of symptoms. (Except for, it should be noted, the necessary amputation of several fingers and toes. Oh, I jest.) Cooling vests entered the scene in the 1980s and started to make MSers reexamine hibernation during the summertime. Today, ActiveMSers considers them an essential tool for managing heat-related symptoms brought on by this disease, as they allow you to explore further, exercise harder, and extract more out of life.

When ActiveMSers first started testing cooling vests years ago, we employed a number of unbiased temperature-related tests to gauge vest effectiveness, but science has dictated subjective reviews may be more appropriate.  Why? Vests/cooling elements start at different temps, and colder is not necessarily better. CJ Skok, as a neurosciences student from Indiana University, wrote a technical white paper on the effects of cooling on multiple sclerosis. He explains the science:

“Thermoregulation, a component of homeostasis, helps maintain optimal temperatures in your body. When the skin is lowered to this low of a temperature, a process called vasoconstriction or the constriction of the superficial blood vessels occurs. Normal skin temperature is typically around 90°F, so vasoconstriction inevitably occurs when you cool your skin to this level. As this happens, less heat is being brought to the skin and thereby less heat can be given off by the body. Thus, while at first this may feel beneficial to the user, it can actually become counterproductive and even potentially dangerous.”

Ranging in price from just a few sawbucks to thousands of dollars, cooling vests/systems can help those with multiple sclerosis maintain cooler core temperatures and lessen the severity of symptoms often caused by heat. Personally, leg weakness and spasticity become issues (my eyes used go wacky but that symptom has faded), but for others, fatigue, cognitive issues, and a host of other symptoms can be backbreaking.

Science Behind Cooling Vests
Dave hiking on a trail with forearm crut


So how do you pick the right vest? What’s the best vest for the dollar? Will the dang thing even work? Good questions, all. Every MSer will have different needs, and not everyone will gain the same benefit. There are no guarantees. Indeed, one vest may have limited effect while another could be a godsend. We at ActiveMSers want to help you make the best, most educated decision possible.


Cooling technology first needs to be broken down into two types: active and passive. Active cooling vests and cooling systems require some form of power (electricity or battery) to operate. They continually provide maximum cooling—many lower the body’s core temperature—and are usually used in the home although they are portable and can be used in the car, the office, etc. These tend to be more expensive systems and generally start around $150 and can run into the four figures.

Passive vests have no working components and are easily portable. Use them basically anywhere your body can go, whether it be on a jog, to the zoo, or to a ballgame. But their cooling power is short-term (30 minutes to 4 hours). While they have limited effectiveness in lowering the core body temperature, passive vests do provide a degree of heat relief helping to abate symptoms brought on by MS. These are the most affordable types of vests, and range in price from $30-$500.

It’s important to note the differences of these types of active and passive cooling vests and systems, as the type of cooling—and the construction of the vest—will drastically affect performance. Additionally, outdoor humidity, ambient temperature, exposure to direct sunlight, and even body temperature of the wearer can influence cooling power. In fact, cooling “power” may not even be much of a benefit, as cooling too much can end up constricting your superficial blood vessels near the skin as your body's natural defense mechanism to warm up kicks in. So your body starts giving out less heat (preserving it, as it thinks it’s getting colder) and you start warming up. Quite the conundrum!

And lastly, realize that the pricier the vest doesn’t always mean the best choice for your particular situation. Likewise, going with the cheap fix might result in nothing more than wasted cash and one extra piece of clothing hanging on that exercise bike you should use more often. You need to weigh what’s most important to you, from convenience to concealability to construction. That said, let’s dive in.

Picking a Cooling Vest

INSURANCE COVERAGE. Most health insurers shrug their shoulders when patients ask if cooling vests are a covered expense. Don't give up. Insurance may cover it if you have a prescription from your doctor (and the VA typically covers vest purchases, active or passive).  Cooling is essential for multiple sclerosis patients and may qualify under Durable Medical Equipment (insurance code E-1399). Still getting denied? The National MS Society has these recommendations for filing an appeal.

COST-FREE VESTS: The Multiple Sclerosis Association of America provides free vests for those with limited incomes (see if you qualify) as does the Multiple Sclerosis Foundation. Some of the vests offered in these programs are highly rated, so please investigate to see if you qualify.

DISCOUNTS: Members of ActiveMSers can save up to 20% on select cooling vests with reserved coupon codes. To get your discount, join today by signing up for our newsletter. NOTE: ActiveMSers has negotiated these discounts and has no other affiliation with these companies and receives no compensation or commission of any kind from them. Some vests were donated for testing purposes.

dave biking with sunflowers in a cooling
Passive Cooling Vests




There is a type of phase change material (PCM) vest that relies primarily on absorbing heat and requires little to no refrigeration and can recharge at room temperature. While these vests don’t dramatically cool you down, they are tuned to prevent you from heating up. Here’s why that matters, according to Mr. Skok. “By having a smaller difference in temperature when compared to skin temperature (i.e. 90°F vs. 82°F), vasoconstriction will not occur and blood flow will continue normally. This allows the transfer of heat from the skin cooling not only superficial blood vessels, but also the core temperature.”

Example: First Line Technology 


+ Stores at room temperature

+ Can be recharged in 10 minutes in ice slurry

+ Generally lightweight and flexible

+ Avoids overcooling the torso



- Doesn’t “feel” cold

- Expensive

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Unlike ice packs, which chill to below freezing, phase change packs maintain much higher temperatures. These phase-change packs often contain liquids (typically nontoxic oils and fats) that solidify like wax, typically between 55 to 70 degrees. In our tests they reliably provide cooling power for as long as 4 hours, the best we've tested. Although these vests don’t “feel” as cold as ice or gel vests, they are working. Due to the higher temps, these vests are comfortable worn directly against the skin. Phase change packs can be recharged in the refrigerator, freezer, cooler, in ice water, or even in a cool room. Typical weight: 2-5 lbs.

Examples: ThermApparel, Glacier Tek, EZ Cooldown


+ Recharges quickly

+ Good for those with cold sensitivity

+ No condensation on packs

+ Long-lasting cooling capacity



- Can be heavy

- Might not "feel" cold

thermapparel white cooling vest.jpg

ThermApparel Undercool is one of our top picks.

TIP: To get the maximum cooling effect from a vest, it should fit snugly around your body. If it hangs loose, some of the cooling power will be lost as you’ll only be chilling air and not your body. Zip up vests must be sized properly to hug your chest. Poncho-style vests, which you wear by putting your head through the center hole and drape over your chest and back, are typically made snug with side straps (usually Velcro).



These vests use cooling sheets that activate when soaked in water and plump when agitated. The user then freezes these sheets, which are dropped into the garment prior to wearing. These vests provide reliable cooling and tend to be lighter in weight than ice or phase change vests. The gel also does not freeze as coldly as ice, so safety is not a concern. Some of these vests can be worn under clothing and may be somewhat concealable. These types of vests typically don’t last as long as PCM or ice vests. Expect about two to three hours of cooling per charge.

Examples: Oro Sports, StaCool Vest


+ Comfortable, consistent cooling power, not too cold

+ Thinner profile means vests could be worn under clothing

+ Replacement gel packs are inexpensive


- Gel packs feel a bit slimy in the first few freeze cycles

- Condensation is common

- Must have access to a freezer to fully recharge

stacool vest gray.jpg



These vests are lined with hydrogel crystals that activate when soaked in water. After the gel ribs plump fully, the vests are towel dried (or put in the spin cycle of your washer) to remove excess water. They are then folded, placed in a plastic bag, and frozen. When removing the vest from the freezer, vests tend to be icy and likely will need some coaxing to fully open. They are among the lightest cooling vests available (second only to evaporative) but have less endurance than phase change, gel inserts, and ice, lasting between 30 minutes to a couple of hours in optimum conditions. Also note that these vests need to be stored cool (in the freezer or fridge) in order for the gel ribs to remain plump or else the user will have to repeat the initial activation process detailed above.

Example: Arctic Heat


+ Can be extremely lightweight

+ Packs down smally when uncharged

+ Typically well-suited for athletics


- Limited cooling capacity, no more than 2 hours when frozen

- Entire vest must be chilled; takes up room in freezer

- Vest can be damp, less practical for day-to-day use

arctic heat cooling vest.jpg

TIP: You can recharge gel/ice packs on the go very fast using this little trick. Fill your cooler with ice. When you want to recharge your packs, add water and a teaspoon or so of salt. Mix it up, and the slurry will super cool those packs faster than even your freezer. The secret is in the salt, which lowers the temp of your slurry to the mid 20s. Please note: you may want to contact your vest’s manufacturer to make sure salt will not damage the gel/ice packs.



These vests are among the most popular and basic in design and tend to provide the most theoretical cooling power among passive vests (which scientific research suggests is not always a positive), with cooling that can reliably last for several hours. The user pre-freezes the ice packs, which are then dropped into pockets on the garment prior to wearing. But our tests have shown that many of these vests can have too much cooling if properly frozen—on par with therapeutic icing for injuries, which should be done for no more than 20 minutes—and in theory could cause frostbite if worn with a single T-shirt. If you find a vest too cold, ActiveMSers recommends these vests be worn with extra layers of clothing for safety, especially if you are already numb in the chest area.

Examples: Steele Vest, Polar Products


+ Affordable

+ Maintains cooling charge longer than many vests

+ Popular with complimentary vest programs for MSers


- Cooling packs often too cold

- Typically heavier than other passive vests

- Must have access to a freezer to fully recharge

steele cooling vest.jpg



Just soak the vest in cool water, then towel or wring dry, and you are ready to go. You’ll likely get a little damp, but that’s to be expected as these vests are essentially portable evaporative coolers that chill the human body. To be effective, the vest should only be worn in low humidity (arid/desert) environments. These are the most affordable passive vests but also typically the least effective. Note: if your home/gym is cooled by an evaporative cooler (swamp cooler), using the vest while the cooler is running will result in little benefit.

Examples: TechNiche HyperKewl, EZ Cooldown


+ Most affordable style of passive vests

+ Quite lightweight, good for sports

+ Easy to recharge (just add water)


- Not effective in humid environments

- Limited cooling capacity

- Vest is damp, could breed bacteria if stored incorrectly

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Active Cooling Vests




Most active vests work by recirculating chilled fluid through the vest being worn by the customer. The vest, which may include a cap, requires a separate cooling unit–a pump to recirculate the fluid and a cooler to hold the ice that chills the fluid–and a power source. Typically these vests run off either A/C or battery power, but fully portable units can use ice water. By reducing the body’s core temperature and providing a constant level of cooling, these vests have been shown in studies to be therapeutic and to reduce MS symptoms in many (but not all) patients. Usually MSers with heat sensitivity will wear this type of cooling garment several times over the course of a day. The vests themselves range greatly in weight, from as little as a few pounds to 10 lbs and heavier. While the vests can be worn during exercise–for instance putting the pump/cooler equipment next to the stationary exercise bike–wearing the vest outdoors is impractical. However, the benefits of the cooling vest may continue to last for a period of time (manufacturers say up to an hour or two) after the vest is removed. Some are portable.

Example: Portable Compcooler, Cool Shirt 


+ Maximum cooling benefit

+ Best of any vest type at dropping core body temperature

+ Effectiveness proven in studies



- Due to power/fluid needs, vests are not very portable

- Vest complexity ups price significantly

- Not practical for most outdoor activity

cool shirt.jpg
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BONUS ADVICE: If a vest remains in your closet because you are too embarrassed to wear it, well, then it is of zero help. So buy what you'll wear (and can afford) and perhaps add a cooling neck wrap or cooling towel to your arsenal against the heat. Pay attention to the manufacturer’s return policy—most are 30 days for a full refund less shipping provided the vests are returned in like-new condition with original packaging.

dave hiking in cooling vest with forearm
ActiveMSers Recommendations


After exhaustively testing more than 20 cooling vests—a vast combination of ice vests, phase change vests, and gel vests (note: active vests have not been tested)—ActiveMSers has uncovered the players from the also-rans in this competitive market.


Vests were judged in 13 objective and subjective categories, ranging from cooling endurance and weight to concealability and comfort. Due to safety concerns and excessive weight, ice vests are generally not recommended; temperatures can plunge below freezing and may trigger numbing and frostbite. Despite their affordability, due to poor performance in humidity, evaporative cooling vests are generally not recommended except for those living in arid conditions. And overall, vests with gel that activates in water are uninspiring, with limited cooling power and uneven cooling performance. Repeated testing has cemented phase change vests as the preferred technology by ActiveMSers. They are the most versatile, since they can be charged in virtually any environment—in the fridge, freezer, ice water, or even in just an air-conditioned home. These are the best-of-the-best and have earned our highest recommendations.

TOP PERFORMER: ThermApparel UnderCool ($200+)


One frustrating fact of cooling vests is that they tend to be bulky, clunky, heavy, and most announce their presence like a 6-pound cyst growing out of your neck. ThermApparel is flipping the script and has designed a vest that is virtually completely hidden, weighs less than two pounds, and lasts longer than many of their larger, full-vest competitors. The UnderCool is ultra lightweight and stretchy, think sheer (and comfy) yoga pants, and comes in a range of sizes and two colors (back or white), cinching at the abdomen with Velcro. Perfect for sports, especially those that involve running. Cooling comes from four phase change (PCM) cooling packs that are inserted into the back of the garment—there is no cooling on the chest. We expected this to be a noticeable negative, but in our testing we still felt refreshed. And a huge side benefit of no cooling packs on the chest: there are no cooling packs on the chest so women (and men) of all chest sizes can wear this comfortably and stealthily. Expect the slim version to last 1-2 hours outdoors on a hot day, 2+ hours when worn indoors. The extended cooling packs add up to an extra hour of cooling power, and is a recommended upgrade.

Weight: 1 lb, 11 oz (2 lbs extended cooling)

thermapparel white cooling vest.jpg

TOP PERFORMER: First Line Technology Standard Mesh Vest ($275+)


At first blush, the Standard Mesh cooling vest from First Line Technology seemed destined to fail. A cooling vest that doesn’t go in the refrigerator, activates at 82.4°F (28°C), and has a reported ultimate cooling effect of a measly 72°F? But it aced every test, every challenge. Concealability? Better than most. Sports? Since it fits so snuggly, the flat PhaseCore panels make it ideal for most active pursuits. Comfort? The panels are not only razor thin, but there are lots of them, so they fit around many body shapes. Convenience? Grab, put on—done. It recharges in a few hours at room temperature (or as little as 10 minutes in ice water). ActiveMSers can't emphasize enough how important this is, as the more time it takes to assemble your vest before you step out of your front door, the less likely you are to bother. The PhaseCore packs last for about 2-2.5 hours before they start to soften, and some may last as long as four hours. Since this vest absorbs body heat, you won’t “feel” cold but you'll notice your vision is still okay, your walking isn’t too bad, your brain isn't fuzzy, and your fatigue isn’t burying you. Note: the PhaseCore panels have a finite lifespan, and will occasionally need to be replaced.

Weight: 3 lbs, 11 oz

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ALSO CONSIDER: Glacier Tek Flex Vest ($220+)


ActiveMSers has long recommended the versatile vests from Glacier Tek. Their original Concealable Cool Vest topped our early reviews but has since been surpassed by other manufacturers. Our current favorite from them is the Flex Vest. It’s a bit hefty weighing in just over 5 lbs, but it’s comfortable, attractive, and long lasting. Expect about 2-2.5 hours of cooling. The vest has seen a minor redesign since our last battery of tests.

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ALSO CONSIDER: Oro Sports CoolSport Vestino ($70+)


Formerly known as Coolture, the original designs from this firm are the brainchild of a former DKNY fashion designer and MSer. Their signature cooling vest is fashion forward and checks many boxes—comfort, fit, design—but we gravitate to their CoolSport Vestino model. Super lightweight at just over one pound, it cools the upper back and is ideal for active pursuits. Concealability and endurance are issues, but can be overlooked at that price.

oro sports coolsport vestino.png

Now that you're geared up for your next adventure or fitness challenge, be sure to check out our guides on travel and exercise as well!

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