Can a Sauna Give You Super Sperm? Bryan Johnson Thinks So

Posted: 7/15/25

Ppl asking for my icing protocol.
+ ice the boys during sauna
+ use a non-toxic, reusable ice pack material
+ I wear cotton boxers and shorts
+ place ice packs in-between boxers/shorts
+ keep in place for the entire session

Posted: 7/10/25

Sauna heat devastated my swimmers.
Seems icing the balls is a good idea.

No ice protection on the boys:
+ 54% drop in motile count
+ 57% drop in motility
+ 55% drop in normal morphology

Conversely, my fertility markers improved from my pre-sauna baseline after 27 sessions with ice on the boys:

+ total motile count ↑ 57%
+ concentration ↑ 26%
+ motility ↑ 16%,
+ morphology ↑ 15%

This aligns with the evidence. Human testes operate 2-4°C cooler than core temp. Even a +2°C rise (from sauna, hot tubs, laptops, etc.) can derail spermatogenesis for 74-days, the length of a full spermatogenic cycle.

What studies show:

+ A single sauna or hot bath at 80-90 °C can drop progressive motility 40-60% two months later.

+ Scrotal cooling devices used in varicocele (overheated testicles from enlarged veins) treatment restore sperm health within 90 days.

A future question we want to address: did my sperm biomarkers improve because of the combination of sauna and ice pack? Or would an ice pack alone deliver similar results?

My sauna protocol is 20 min daily at 200°F.

Posted: 6/2/25

We’re used to seeing the sauna and cold plunge as a power duo for recovery, but tech entrepreneur and human performance experimenter Bryan Johnson just added an unexpected twist: fertility gains.

In a recent tweet, Bryan shared:

“21 sessions at 20 min, 200°F sauna dramatically improved my fertility health. I iced the boys to protect them, didn’t anticipate that markers would improve.”

Yes, you read that right. He used high-heat sauna sessions while literally icing his groin to safeguard sperm health. And the results? Better fertility markers.

So...Does Sauna Hurt or Help Sperm?

Traditionally, we’ve heard heat is bad news for sperm and for good reason. Studies show that regular sauna use can temporarily lower sperm count and motility. The body needs cooler temps for sperm production, which is why the testes naturally sit outside the body. In one clinical study, men who used a sauna twice a week for three months saw measurable drops in sperm health (though things bounced back after they stopped).

But Bryan’s approach flips the script. Instead of avoiding the heat, he embraced it - with a side of cold.

Icing the Boys: Smart or Just Savage?

By using targeted cold exposure (aka ice packs) during high-heat sauna sessions, Bryan may have found a workaround. The cold likely protected testicular temperature, while the sauna delivered its usual benefits: detoxification, circulation, stress reduction, and cardiovascular support.

And if you’re thinking, “There has to be a better way than holding an ice pack in the sauna…” - you’re in luck.

There is.

It’s called vasectomy recovery underwear, and yes, you can absolutely wear them in the sauna. Designed to hold ice packs exactly where you need them, they might just be Bryan Johnson - approved biohacking gear for the rest of us.

What This Means for You

At Plunge, we’re big fans of smart recovery routines. That means listening to your body, dialing in your protocols, and testing what works for you. If fertility is part of your health goals, consider these tips:

• Be mindful of heat exposure - especially duration and frequency.

• Explore contrast therapy (hot sauna + cold plunge) to maximize benefits while minimizing downsides.

• If you’re concerned about sperm health, consult your doctor before locking in a new sauna schedule.

Bottom line: Heat can stress the system - but when paired with cold and intention, it might actually help the body recalibrate in surprising ways. Bryan’s story is a nudge to keep exploring the edge of what’s possible. Just don’t forget the ice.