Adventures in Palm Cooling for Strength Gains

It’s like a performance enhancing drug… but without the drug.

Mar 25, 2022
A couple of months ago I was listening to the Huberman Lab podcast where Dr. Huberman explains that cooling your palms between exercise sets dramatically improves work volume and strength training response. 
He described the work of Dr. Craig Heller and Dennis Grahn, biologists at Stanford. 
The results he describes were staggering. 
We’re talking about being able to perform 200-600% more volume–repetitions of resistance exercises–in a span of 6 weeks. 
My eyes were wide open. I might have been drooling. 
How do I do this novel palm cooling?

Gaining muscle is hard work.

There are very few shortcuts and those that exist will probably kill you. 
Worse… after a few years of training, it becomes even harder to build muscle and gain strength. 
This doesn’t bother me… but if there is a way to improve more faster in a safe way… I’ll take it! 
Let’s step back for a moment. 
Why in the heck will cooling your palms help you get stronger or do more lifting volume than you could otherwise?
In turns out, there is an optimal temperature for muscle function. When our body heats up, the contractile force capacity of muscle decreases rapidly. 
It’s very difficult to quickly change our temperature. But there are special parts of the body that are able to transfer heat fast: our cheeks, bottoms of the feet, and palms. These areas–known as glabrous skin–contain arteriovenous anastomoses (AVA), which are direct connections between small arteries and small veins. 
In several studies–here is one–Dr. Craig Heller and team demonstrated that extracting heat from the body between exercise sets increased work volume (the number of reps performed) by 144% (pull ups) and increased strength gains by 22% (bench press) over 6 weeks. 
We’re all drooling right? 
So how do we do this?! 
In the podcast, Huberman describes the “protocol” aka how to do this palm cooling. 
Unfortunately, it’s not as simple as sticking your hands in cold water between sets. If you plunge your hands in cold water, those AVA will vasoconstrict–tightening to the point where blood will not flow well.
And even if you have the right temperature, if you were only to stick your hands in a bucket, a temperature barrier would form that would prevent the offloading of heat from your palms into the water. 
In the lab, they built a special device to cool people’s palms–which I believe they are commercializing. 
However, in the spirit of zero cost education, Huberman and Heller hypothesized that you could hack this at home by getting a bucket of correctly cooled water and moving your hands through it constantly to prevent the barrier from being formed. 
I tried this. And naturally, I tweeted about it too in October 2021. Complete with a video in which I also demonstrate my unique sense of fashion. 
I didn’t think I was doing it right. Life got busy and the potential for safe, yet staggering gains slipped my mind. 
Flash forward to February, I got a reply to said Tweet from a Physics PhD who had built his own palm cooling device and had been seeing great results.
It turns out Ariel Paul lives an hour away from me and was happy to share how it works. 🤯

A Trek to Boulder In Search of Gains

A week ago, we went out to meet him. He set up V2 of his prototype for me in his home gym and left me to do my thing while he and Dane went off to build another version of the prototype … get this… for me to take home!
For 1 hour and 22 minutes, I worked through 10 sets of pushups and 10 sets of pullups. 
Between each set, I sat calmly on a bench holding the cooling device gently in my hands for 3 minutes pondering how wild this whole thing is… and just how much I love Twitter.  
My results shocked me. 
Pushups: 20-20-20-20-20-17-15-15-12-10: 169 rep Pull-ups: 7-7-7-7-6-6-6-6-6-6: 64 reps
While I realize I should have tested without the palm cooling before, I didn’t. But I did redo it this week sans cooling just to see. 
Pushups: 20-20-20-19-18-16-16-15-13-12: 169 reps Pull-ups: 7-7-6-5-6-5-5-5-5-5: 56 total reps
My pushup rep count was the same. However, it is possible that the one palm cooling session helped me over a plateau. I’ll never know and can only see where I go from here and how fast I improve. 
But woooow. I did 14% more pull ups with the cooling. That is incredible. Yes, one data point, but exciting nonetheless. 
So here’s my game plan.
Next week, I’ll do a 1 rep max test on a bunch of my lifts to set my baseline. 
The week of April 4th, I’m traveling so it’ll be a deload week. 
Starting April 11 for at least six weeks, I’ll follow this program, inspired by the studies. I’m prioritize strength in some lifts and work volume in others.
In all cases, I will rest for 3 minutes while holding the device. 


Back Squat: 
  • Set 1: 10 reps at 40%
  • Set 2: 7 reps at 60%
  • Set 3: 4 reps at 80%
  • Set 4: 2 reps at 95% (if successful - all goes up next time by 5#)
  • Set 5: 5 reps at 60%
  • Set 6: 10 reps at 40% Pull-ups: 
  • 10 sets to failure  Accessory Work: 
  • Quads 
  • Core


  • Set 1: 10 reps at 40%
  • Set 2: 7 reps at 60%
  • Set 3: 4 reps at 80%
  • Set 4: 2 reps at 95% (if successful - all goes up next time by 5#)
  • Set 5: 5 reps at 60%
  • Set 6: 10 reps at 40% Pushups: 
  • 10 sets to failure  Accessory Work: 
  • Hamstrings 
  • Glutes
  • Shoulders 






Repeat Back Squat & Pull-Up Day


Repeat Deadlift & Push-Up Day


Run or Row
In the subsequent 6 weeks, I plan to do upper body strength work (bench press and shoulder press) and lower body volume (squat and deadlift). 
Phew! If you’ve made it through this post, thank you and 👏. 
You can rest assured I’ll keep you posted here and on Instagram @thepleasantbox.  
Coolest Person of the Year Award goes to Ariel for making me my own palm cooling device. I’d like to write more about how it works in the future. 
But for now, let the gains begin!