Leading experts are pointing to this sauna breakthrough
Longevity researchers and biohackers agree — reducing heat exposure where it matters most is no longer optional.
Bryan Johnson
@_bryan_johnson_
Longevity protocols and the importance of testicular cooling
HealthMaxx
@healthmaxx_clips
The case for cooling during sauna — what the research shows
Dr. Paul Saladino
@paulsaladinomd2
On why men should protect against heat exposure in the sauna
These creators are not affiliated with CULMIN. Videos are embedded from TikTok.
The biology behind it
The part of sauna most men never think about
Prolonged groin heat during sauna lowers sperm quality, disrupts hormonal balance, and affects long-term male health.
Prolonged groin heat during sauna triggers three biological responses:
Spermatogenesis disruption — heat impairs sperm production at the cellular level.
Leydig cell damage — the cells responsible for 95% of your testosterone are weakened by sustained heat exposure.
HPG axis suppression — the hormonal signaling chain that drives testosterone production shuts down.
A study by Garolla et al. demonstrated that sauna use just twice a week for three months resulted in a 50% decrease in sperm count and significant alterations in mitochondrial function.
The damage is measurable, reproducible, and directly tied to sustained heat exposure in the groin area. That is not extreme use — that is a normal routine.
CULMIN is for men who want the full benefits of sauna — without the trade-off below the waist.
Each pair comes with a built-in cooling insert that reduces heat where it matters — during every session.
No improvisation. No compromise. Just a more considered way to sauna.
Sauna without the trade-off.
Shop CULMINYour sauna protocol
How CULMIN works
A simple four-step protocol that integrates into any sauna routine.
Place both cooling inserts in your freezer. They're ready in about an hour.
Put on CULMIN and slide one frozen insert into the built-in pocket. It sits securely and stays in place.
Use your sauna normally. The insert reduces localized heat where it matters throughout your full session.
Remove the insert, rinse, and refreeze. The second insert is already waiting — ready for your next session.
Why CULMIN
The deliberate alternative
What sauna users are saying
Built for men who take sauna seriously
"I sauna 4-5 times a week and always wondered if the heat was doing damage down there. CULMIN is the first product that actually addresses it without being weird about it."
"My wife and I are planning to start a family. When I learned what sauna heat can do to sperm quality, I started looking for a solution. This is the only one that feels premium enough to actually use."
"The inserts stay cold for a solid 20-25 minutes which is my full session. Fits like normal boxer briefs. Exactly what I wanted."
"Honestly thought this was overkill until I read the research. Now it's part of every session. Simple, discreet, and I don't have to think about it."
"Bought one for myself and another for my brother. He saunas every day and never thought about this. Now he won't go without it."
"I've been in the sauna community for years and nobody talks about this. The fact that this exists now is a no-brainer."
Common questions
Everything you need to know
CULMIN is a premium cooling boxer brief designed for sauna use. Each pair includes an integrated pocket and two reusable BPA-free cooling inserts. You freeze both inserts before your session, slide one into the pocket, and wear CULMIN during your sauna. The inserts reduce localized groin heat while you get the full benefits of your session.
The testes are positioned outside the body because sperm production and hormonal function require temperatures 3–7°F below core body temperature. A sauna session regularly exceeds 176°F, raising groin temperature well beyond its ideal range. Research shows that repeated heat exposure in this area can reduce sperm count, motility, and affect hormonal markers. CULMIN helps men reduce that unnecessary exposure.
The inserts provide effective cooling for approximately 20–30 minutes depending on sauna temperature. That covers a typical full sauna session. Each pair comes with two inserts — use one per session, and the second is already frozen for your next one.
Yes. CULMIN is made from premium breathable cotton with a seamless construction designed for heat environments. The cooling inserts sit in a discreet pocket and stay in place — you'll feel the cooling benefit without bulk or discomfort. It wears like high-quality boxer briefs.
Yes. Groin heat doesn't just affect fertility — it can impact hormonal health, testosterone levels, and overall male reproductive function regardless of whether you're planning to conceive. CULMIN is for any man who wants the full benefits of sauna without the heat working against him.
We offer a 30-day satisfaction guarantee. If CULMIN doesn't change how you sauna, return it for a full refund. No questions, no hassle.
Machine wash cold with like colors, tumble dry low. The cooling inserts should be rinsed after use and stored in the freezer between sessions. The briefs are built to hold up to regular washing without losing shape or function.
Yes. CULMIN is designed for sauna use, but you can absolutely wear it during cold plunges or ice baths. The boxer briefs are made from breathable, durable fabric that performs well in both heat and cold. The cooling inserts are only needed for sauna sessions.
Yes. We currently ship to the United States, Canada, and Australia. Orders are processed within 1–3 business days, and delivery times vary by destination. Shipping costs are calculated at checkout.
Start your protocol
Sauna is intentional. Your protection should be too.
Same routine. Smarter protection. Better outcomes.
Shop CULMIN30-day satisfaction guarantee. Try CULMIN for a full month. If it doesn't change how you sauna, return it for a complete refund. No questions asked.