knowledge base

The Science of Palm Cooling & Warming

Learn all about how the body heats up, cools down and performs at its peak.

TL;DR

Palm cooling & warming works by targeting clusters of blood vessels in the palms. Cooling lowers core temperature, delays fatigue, and boosts endurance and strength. Warming reverses hormonal and environmental chills.
Science has shown palm cooling helps with:
Athletic performance:
Athletic performance:

Stanford studies show palm cooling can increase endurance by ~15% and strength training work volume by up to 144%.

Menopause relief:
Menopause relief:

Clinical trials show that effectively lowering core body temperature can reduce the intensity and duration of menopausal hot flashes. Cryo-1's warming mode also provides quick comfort for sudden hormonal chills, helping restore circulation and balance.

Outdoor heat stress:
Outdoor heat stress:

Golfers, firefighters, soldiers, and outdoor workers can use palm cooling recover faster, lower heart rates, and return to work more safely.

Anxiety & vagus nerve cooling:
Anxiety & vagus nerve cooling:

Cooling palms and lateral neck areas can lower heart rate, activating the parasympathetic nervous system, and reduce panic symptoms.

Palm Cooling Origins

A History of Discovery and Effectiveness

Palm cooling wasn’t born in sports science — it was discovered in medicine. Surgeons learned during open-heart procedures that patients who couldn’t be covered could be rewarmed by heating their palms and soles, revealing unique heat exchange pathways.

Later research confirmed that these glabrous skin areas work as natural radiators, capable of rapidly moving heat in or out of the body. This insight became the foundation of palm cooling for performance and safety. Comparing it with neck cooling shows why palm cooling is more than comfort — it’s physiology.

Medical Origins in Surgery
Medical Origins in Surgery

Doctors found that warming the palms and soles helped patients recover faster from open-heart surgery when their torsos were exposed.

This was the first evidence that these skin regions were gateways for managing core body temperature.

The Shift to Cooling
The Shift to Cooling

Once the mechanism was known, scientists tested the reverse: cooling the palms.

They found it lowered core temperature more effectively than surface methods like towels or fans, slowing fatigue and strain during exercise in the heat.

Neck Cooling vs. Palm Cooling
Neck Cooling vs. Palm Cooling

Studies show that neck cooling mostly improves comfort, reducing perceived exertion but rarely changing heart rate, lactate levels, or core temperature.

Palm cooling, by contrast, directly reduces physiological strain, measurably improving endurance and recovery.

Real-World Application
Real-World Application

Palm cooling has since been tested in athletes, firefighters, and workers.

It consistently lowers heart rate, improves work volume, and accelerates recovery — proving that what started as a surgical trick is now a practical tool for performance and safety.

Athletic Performance

Real Results & Data

Athletic performance is often limited not by muscle or willpower, but by the body’s rising core temperature. As heat builds, fatigue sets in faster and recovery slows. Palm cooling directly targets this bottleneck by lowering thermal strain, allowing athletes to push past limits that would otherwise hold them back.

This effect has been studied broadly at Stanford and other institutions, with controlled trials consistently showing that cooling the palms can delay fatigue, extend endurance, and improve strength outcomes.

Conclusion: Palm cooling removes a hidden ceiling imposed by heat, allowing athletes to perform longer, recover faster, and achieve greater strength gains.

Palm Cooling Extends Endurance in Heat
Palm Cooling Extends Endurance in Heat
Grahn et al., 2005

In treadmill trials at 40°C, palm cooling alone extended exercise duration by about 15% compared to control.

This meant participants were able to keep walking on an incline treadmill for several minutes longer before reaching exhaustion.

The effect showed that cooling the palms slowed the rise in body temperature and delayed fatigue, even in extreme heat

Read the study
Palm Cooling Increases Training Volume
Palm Cooling Increases Training Volume
Grahn et al., 2012

In resistance training, palm cooling had a major effect on performance.

Over a 10‑week program, participants who cooled their palms between sets completed 40% more work on bench press exercises compared to controls. Pull‑up training volume grew by 144%, showing that cooling allowed athletes to keep performing at higher levels for longer.

Strength also improved, with one‑rep max (1RM) increasing by 22% during the study

Read the study
Palm Cooling Boosts Repetition Capacity
Palm Cooling Boosts Repetition Capacity
Dip Study (2021)

A San Francisco 49ers tight end completed 103 total dips across five sets without cooling. With cooling between sets, his total rose to 198 dips in the same session—an increase of 92 dips.

Over four weeks of training with cooling, he progressed further to 310 dips per workout, a total increase of 207 dips from baseline.

Read the study
Palm Cooling Improves Strength Progression
Palm Cooling Improves Strength Progression
Bench Press Study (2021)

A tight end for the Oakland Raiders performed six sets of 225 lb bench presses. His baseline was 51 total reps. After three weeks with cooling, output rose to 60 reps (17.6% improvement).

Over the next four weeks without cooling, gains held steady but did not increase. When cooling resumed for two weeks, performance rose again to 67 reps—a total 31.4% improvement over baseline.

Read the study

Hot Flash & Chill Relief

Menopause & Hormonal shifts

Menopause brings profound changes to the body’s temperature regulation. This area has been studied in both clinical trials and review articles, with consistent evidence that cooling & warming interventions can provide meaningful relief.

Fluctuating estrogen levels narrow the hypothalamus’ thermal comfort zone, making women more prone to sudden waves of heat and chills. Hot flashes and cold spells are not just uncomfortable—they disrupt sleep, work, and confidence. Palm cooling offers a direct physiological way to draw off excess heat during hot flashes, while palm warming helps reopen blood vessels and restore warmth during sudden chills - stabilizing your body’s temperature from both directions.

Conclusion: Targeted cooling and warming provide fast, discreet relief for menopause’s most disruptive symptoms, improving daily life and sleep quality without medication risks.

Menopause Narrows the Thermal Comfort Zone
Menopause Narrows the Thermal Comfort Zone
Freedman (2001)

Physiological studies suggest palm cooling works by widening the narrowed “thermoneutral zone” caused by low estrogen, allowing excess heat to offload through the palms.

The hypothalamus, which regulates body temperature, becomes oversensitive in menopause, so even small rises in core temperature can trigger a hot flash.

Research by Freedman and colleagues has shown that postmenopausal women have a much narrower thermoneutral zone, meaning very slight changes in core temperature can set off this hypothalamic response

Read the study
Palm Cooling Stabilizes the Body’s Thermostat
Palm Cooling Stabilizes the Body’s Thermostat
Freedman (2005)

Laboratory research outside of Freedman’s early studies shows that the hypothalamus acts like a thermostat that can become unstable in menopause, causing sudden bursts of heat release.

Palm cooling removes heat directly from the bloodstream, helping to stabilize this thermostat. As a result, women experience fewer episodes of rapid overheating and the uncomfortable waves of sweating that follow

Read the study
Clinical Trial Confirms Palm Cooling Relief
Clinical Trial Confirms Palm Cooling Relief
Reid et al., (2015)

A 2015 study tested a handheld cooling device (Menopod®) applied to the neck for hot flash relief. Results showed limited effectiveness, highlighting that surface cooling on non AVA rich skin alone doesn’t meaningfully lower core temperature.

Still, it supported the link between reduced core temperature and fewer or milder flashes. Cryo-1 applies this same proven principle but uses palm cooling — the Stanford-validated method that directly cools the blood and rapidly stabilizes core temperature.

In Cryomedics’ own user trials, 100% of women reported noticeable relief, with most feeling cooler within 60 seconds.

Read the study
Peripheral Warming Relieves Menopausal Chills
Peripheral Warming Relieves Menopausal Chills
Gombert-Labedens et al. (2025 Review)

Early human and physiology data show that during menopause, drops in estrogen heighten sensitivity to cold and trigger chills. Though direct trials of warming interventions are still emerging, this review notes that warming peripheral skin - especially areas rich in AVAs (arteriovenous anastomoses) like the palms - can help restore thermal comfort by improving circulation and reducing cold sensations. Many women reported relief from cold sweats and shivering when warming strategies were used.

Read the study

Heat Stress

& Outdoor Worker Safety Research & Data

Extreme heat challenges not only athletes but also millions of workers, first responders, and people at outdoor events. Research across occupational health and emergency response has shown that palm cooling is an effective way to lower physiological strain in real-world conditions. As body temperature rises, concentration drops, fatigue accelerates, and safety risks climb.

Conventional fixes like fans or ice packs provide surface comfort but do little to lower core heat. Palm cooling addresses this gap by reducing thermal strain from the inside out.

Conclusion: For workers, first responders, and outdoor enthusiasts, palm cooling is a practical safety tool that improves performance, recovery, and resilience in heat.

Hot worker
Heat Stress Reduces Worker Productivity
Han et al., (2024)

A meta-analysis of over a dozen studies covering ~2,400 construction workers found that when wet-bulb globe temperature rose above 28 °C, about 60% of workers showed reduced productivity due to heat stress.

This means that in hot conditions, most workers slowed down, took more breaks, or were unable to finish their normal workloads. Even modest increases in temperature had clear effects on both safety and economic output.

Read the study
Active Cooling Speeds Firefighter Recovery
Active Cooling Speeds Firefighter Recovery
Burgess et al., (2012)

Research on live-fire drills shows firefighters’ core temperature and heart rate rise rapidly under heat and exertion.

In these studies, firefighters who used active cooling methods—such as applying cooled water or holding cooled devices during rehab—saw their core temperatures drop faster and their heart rates return to baseline more quickly than those who only rested.

This demonstrates that active cooling can significantly speed recovery compared to passive rest alone

Read the study
Heat Stress Costs Billions in Lost Work
Heat Stress Costs Billions in Lost Work
American Progress 2024

The International Labour Organization estimates that countries may lose 2–5% of working hours in high-heat sectors by mid-century without better mitigation (ILO). This loss translates into hundreds of billions of dollars in global economic impact, as fewer working hours mean less output and higher costs for businesses.

In the United States alone, heat stress is already estimated to cost employers around $100 billion per year, primarily through lost productivity, absenteeism, and higher healthcare expenses (FAS).

Projections suggest this could double to $200 billion annually by 2030 and climb as high as $500 billion by 2050 without intervention

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Outdoor Athletes at Risk of Heat Exhaustion
Outdoor Athletes at Risk of Heat Exhaustion
Nagashima et al., (2025)

A recent study of amateur golfers reported a high risk of exertional heat exhaustion in hot and humid conditions, especially with poor hydration and limited rest.

The researchers found that players frequently experienced elevated heart rates, dizziness, and reduced performance when playing in high heat without proper cooling or recovery breaks.

By slowing the rise of core temperature and easing cardiovascular strain, palm cooling may help golfers, pickleball players, and other outdoor athletes avoid hitting these dangerous thresholds.

Read the study

Anxiety

Vagus Nerve Cooling, & Heart Rate Regulation

Anxiety is more than a mental state—it is a full-body surge of sympathetic activation. Studies in physiology and clinical psychology have demonstrated that targeted cooling of the palms and neck can influence vagal tone and cardiovascular response, offering a physiological pathway to relief. The heart races, breathing shortens, and many people feel overheated.

By cooling the palms, the body sheds heat and reduces sympathetic load. When paired with gentle cooling along the lateral neck, vagus nerve pathways are stimulated, which helps slow heart rate and promote calm.

Conclusion: Combining palm and vagus nerve cooling offers a simple, drug-free way to interrupt anxiety cascades and bring the body back into balance.

Cold Immersion Reduces Panic Symptoms
Cold Immersion Reduces Panic Symptoms
Xie et al., (2021)

A 2021 clinical study examined patients with panic disorder undergoing short cold facial immersion.

The cold exposure activated the diving reflex, which produced a marked drop in heart rate and increased parasympathetic activity compared to baseline.

Participants reported reduced panic symptoms during the intervention, showing that targeted cooling can directly calm the cardiovascular system and ease anxiety responses.

Read the study
Neck Cooling Lowers Heart Rate and Boosts HRV
Neck Cooling Lowers Heart Rate and Boosts HRV
Jungmann et al., (2018)

A randomized trial with 61 healthy participants tested cold stimulation on the lateral neck, cheek, and forearm.

Cooling applied to the lateral neck for 16‑second intervals significantly increased heart rate variability and lowered heart rate compared to baseline.

This shows that targeted cooling in this area can directly activate the parasympathetic nervous system 

Read the study
Cooling Aids Recovery After Intense Exercise
Cooling Aids Recovery After Intense Exercise
Choi, Roh & Cho (2023)

A study of adolescent cyclists tested neck cooling at different temperatures during high‑intensity training.

Cooling reduced perceived heat, lowered ear temperature, decreased heart rate during recovery, and reduced stress markers in the blood.

This suggests cooling the neck helps the body recover faster from cardio and systemically induced stress.

Read the study
Extended Neck Cooling Slows Heart Rate
Extended Neck Cooling Slows Heart Rate
Kohn et al., (2020)

A 2020 study tested 11 healthy adults with 90 minutes of localized neck cooling.

Neck skin temperature dropped by about 9 °C, and participants’ heart rates slowed significantly during the cooling period.

This shows that neck cooling can directly reduce cardiovascular strain by activating the body’s natural reflexes for conserving energy 

Read the study

Cryomedics Solutions

Science you can hold

Cryo turns decades of research on palm and vagus nerve cooling & warming into a simple handheld device. Backed by clinical and athletic trials, it helps improve performance, reduce hot flashes, reverse chills, ease anxiety, and fight heat stress. Explore the products below and see how cooling science fits your life.

References

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  2. Grahn DA, Cao VH, Nguyen CM, Liu MT, Heller HC. J Strength Cond Res. 2012. PubMed
  3. Reid RL et al. Randomized clinical trial of handheld cooling device. Climacteric. 2015. PubMed
  4. Heller HC, Grahn DA. Stanford Research Reports, 2012–2017. Researchgate
  5. Freedman RR. Physiology of hot flashes. Am J Hum Biol. 2001. PubMed
  6. Freedman RR. Menopausal hot flashes: mechanisms, endocrinology, treatment. Thieme. 2005. Thieme
  7. Koehn J et al. Neck cooling induces blood pressure increase and peripheral vasoconstriction in healthy persons. Auton Neurosci. 2020. PubMed
  8. Venugopal V et al. Heat stress and its impact on productivity of workers: a meta-analysis. Int J Environ Res Public Health. 2022. PMC
  9. Hostler D et al. Firefighter rehabilitation with active cooling during live-fire training. Prehosp Emerg Care. 2013. PubMed
  10. Brearley M et al. Exertional heat illness in golfers: risk factors and prevention. J Sports Sci. 2025. Taylor & Francis
  11. International Labour Organization. Working on a warmer planet: The impact of heat stress on labour productivity. ILO Report. 2019. ILO
  12. Center for American Progress. Extreme heat is more dangerous for workers every year. 2019. American Progress
  13. Federation of American Scientists. Impacts of extreme heat on labor productivity. 2021. FAS
  14. Müller T et al. Brief cold stimulation of the neck region increases HRV and reduces heart rate. Front Physiol.2019. PubMed
  15. Azevedo TM et al. Cold facial immersion reduces panic symptoms via diving reflex in panic disorder patients. Front Psychol. 2021. PubMed
  16. Lee JY et al. Neck cooling during high-intensity exercise reduces heat strain and stress markers in adolescent athletes. Life (Basel). 2023. MDPI
  17. Effects of menopause on temperature regulation. Temperature V12 2025