AVA Cooling Tech Palm Cooling Device

Two Palm Cooling Tests Demonstrate Significant Performance Improvements

There is a growing amount of research demonstrating the positive effects of palm cooling in relation to delaying the onset of fatigue and improving overall performance while working out. This performance boost is being seen in both the short term (single session workouts) and long term (increased training volume over time). What does this mean? It means people who are palm cooling between their sets of exercises are performing far more reps and sets compared to those who are doing the same workouts but are only passively resting between their sets. 

This research was kicked off by Dr. Keller at Stanford but has now been replicated by other researchers. We found an awesome video on YouTube by House of Hypertrophy that gives a great explanation of the science and also a digestable review of the research. Check out that video here:

If you are like me, when you learn about performance enhancement hacks you become very skeptical. I know when I first learned about palm cooling on the Joe Rogan Experience Podcast with Dr. Huberman episode I didn't believe that palm cooling could have the effects they were proclaiming. So, as any self respecting scientist, physical therapist or strength coach would do I decided to make my own cooling device and test the theory out myself. 

Here's what happened with my palm cooling testing:

Test 1: 7 Sets of seated shoulder presses with 3 minutes of rest between sets

For this test I wanted to use a similar protocol to that used by Dr. Keller at Stanford when he originally tested the NFL player. His subject did sets to failure of dips with a 3 minute rest break between sets. His subject had a 60% improvement in performance when using palm cooling compared to when he did not. Most of that improvement was because the athlete was allowed to keep doing more sets when using the palm cooling. The subject simply felt that he could keep adding sets after each break with cooling where as without the cooling he motivation to continue going waned relatively quickly. So, for my test I wanted to see if there would be an improvement if I was only allowed to do the same number of sets (7) with reps to failure when cooling or not. I chose the seated shoulder press because I did not want to be able to use the legs for assistance as I started to fatigue. I used two, 25lb dumbbells for resistance as I knew I could do a fairly high number of reps per set and this would help me detect smaller changes than if I used weights that were relatively heavier for me.  Finally, I did these tests on consecutive days at the same time of day and with basically the same nutrition beforehand. I wanted the palm cooling day to be on the second day (when I would be more fatigued) so as to not give that test day any advantage and actually put it at a disadvantage. 

Results of test 1: 

  • Without palm cooling on day 1: 128 reps performed over 7 sets
  • With palm cooling on day 2: 150 reps performed over 7 sets
  • This equals at 15% improvement on day 2 with palm cooling added

Test 2: 20 Seated row reps per set, 1 minute rest between sets, no cap on number of sets

During my first test I felt that the 3 minute rest break was a lot of time for me to recover on both the cooling and non cooling days. While I was very happy with the 15% improvement in test 1, I thought that maybe if I got my heart rate up a little higher (increased body heat) and had a shorter rest break that I might see a bigger difference in how the palm cooling affected my performance. So, for test 2 I decided that I would do the same number of reps each round and see if I could last more rounds with palm cooling vs without. I would use form fatigue as my cue to stop the test. I did a seated cable row with a form standard of being able get my thumbs to my ribs with each row to count as a good rep. I performed 20 of these reps every round with 70 lbs of resistance and then immediately stood up and did 20 jumping split lunges to spike my heart rate. I then rested for 1 minute. I used palm cooling on day 1 and then 5 days later repeated the test without palm cooling. Again, I did this at roughly the same time of day with the same amount of activity prior to the test. The big difference with this test from the first was that there was no preconceived set limit. I would simply keep doing sets until I could no longer get my thumbs to my ribs on a seated row rep.

Results of Test 2:   

  • With palm cooling I was able to do 219 reps of the row before I failed (10 rounds + 19 reps)
  • Without palm cooling I was able to do 158 reps (7 rounds + 18 reps)
  • This equals 61 more reps prior to form fatigue with palm cooling, a 28% performance boost. 

The results of my two different tests were quite surprising to me. I doubted that there would be any benefit going into the first test. I train a lot. I work very hard when I train and I didn't think that holding something cool in my palms during rest breaks would make any difference. It did in both testing situations. One with an upper body push and long rest breaks and the other with an upper body pull, a heart elevating jumping lunge, and shorter rest breaks. Both situations demonstrated the ability of hand cooling to delay fatigue and improve performance at percentages that anyone working out or competing would love to experience. 

 We'll keep testing, reading, learning and experimenting. For now though, we can confidently say that the real world testing is showing benefits similar to the research lab. 

Let us know your thoughts.

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