Controlled heat and cold exposure trigger powerful adaptive responses: heat shock proteins that repair cells, cold shock proteins that sharpen your brain, cardiovascular conditioning, metabolic activation, and resilience you can feel.
But the dose matters. Too little, nothing happens. Too much, you’re just suffering.
TempRx calculates your optimal exposure time based on the variables that actually matter — temperature, humidity, duration, modality, and body coverage. No guesswork. No vibes. Just the science of thermal therapy, translated into a number you can use.
Select your modality. Dial in your settings. Get your target.
Why This Works
Your body adapts to stress. That’s the principle behind exercise, vaccines, even sunlight — small, controlled doses trigger protective responses that make you stronger.
Heat and cold work the same way.
Heat stress (sauna, steam room, hot tub) raises your core temperature, triggering heat shock proteins that repair damaged cells, reduce inflammation, and improve cardiovascular function. Finnish studies found that people who used saunas 4-7 times per week had 40% lower all-cause mortality.
Cold stress (cold plunge, cold shower, cryotherapy) spikes norepinephrine by 200-300%, improving focus, mood, and energy for hours. It activates brown fat for metabolic benefits and produces cold shock proteins that support brain health.
The catch? The dose depends on your setup. A 185°F dry sauna and a 115°F steam room require completely different exposure times to hit the same threshold. A 40°F plunge and a 55°F cold shower aren’t interchangeable.
TempRx does the math so you don’t have to.
What TempRx Measures
For Heat:
HSP (Heat Shock Proteins): Cellular repair and stress protection
Longevity: Markers associated with reduced mortality risk
For Cold:
CSP (Cold Shock Proteins): Cellular protection and resilience
BAT (Brown Adipose Tissue): Metabolic activation and fat burning
BDNF (Brain-Derived Neurotrophic Factor): Mental clarity and mood
How to Use TempRx
Choose your modality — Dry sauna, steam room, hot tub, cold plunge, cold shower, or cryotherapy
Set your temperature — Match your actual environment
Adjust humidity or body coverage — Depending on heat or cold
Set your duration — See how your session stacks up
Hit your targets — Aim for strong activation across the markers that matter to you
The calculator shows your estimated time to reach meaningful activation thresholds based on the best available research. Individual responses vary — this is a guide, not a prescription.
The Research Behind TempRx
This isn’t guesswork. TempRx is built on peer-reviewed studies in thermoregulation, heat shock protein activation, cold thermogenesis, and human cooling/heating curves.
Key sources include:
The Kuopio Ischemic Heart Disease Study (20+ years of Finnish sauna data)
Dr. Susanna Søberg’s cold exposure research
Dr. Rhonda Patrick’s work on heat shock proteins
Controlled trials on cold water immersion and norepinephrine response
Want to go deeper? Explore the full TempRx blog series for the science behind each modality, optimal protocols, and how to build your weekly thermal routine.
The best saunas, cold plunges, and contrast therapy spots in Nashville — from a seven-sauna Finnish studio in Wedgewood-Houston to a 40-person communal sauna with guided breathwork in East Nashville. Curated by TempRx, because the dose matters.
The best saunas, cold plunges, and contrast therapy spots in Miami — from the largest authentic Turkish hammam in the US to a Belle Isle bathhouse with an arctic plunge on Biscayne Bay. Curated by TempRx, because the dose matters.
The best saunas, cold plunges, and contrast therapy spots in Austin — from 230°F outdoor cedar saunas on South Lamar to the #1 destination spa in the country on Lake Austin. Curated by TempRx, because the dose matters.
The best saunas, cold plunges, and contrast therapy spots in Denver — from a nude Russian sauna running since 1927 to mile-high recovery studios and cold plunges at altitude. Curated by TempRx, because the dose matters.
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The best saunas, cold plunges, and contrast therapy spots in San Francisco — from floating saunas on the Bay to a silent Japanese bathhouse in Japantown. Curated by TempRx, because the dose matters.
TempRx Series | Part 12 of 12 You’ve made it through the science. Heat shock proteins. Cold shock proteins. Brown fat activation. BDNF. Cardiovascular conditioning. The Søberg protocol. Contrast therapy. Finnish mortality data. Neurochemical cascades. Now comes the question that actually matters: what do you do with all of this? Knowledge without application is just…
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TempRx Series | Part 11 of 12 So far, we’ve treated heat and cold as separate interventions. Sauna for cellular repair and cardiovascular health. Cold for neurochemical activation and metabolic boost. But what if you did both? Contrast therapy — alternating between hot and cold — isn’t a modern biohack. It’s ancient practice. Roman baths…
The best saunas, cold plunges, and contrast therapy spots in Los Angeles — from 24/7 Korean jimjilbangs in Koreatown to backyard sauna studios in Venice. Curated by TempRx, because the dose matters.