Peat rarely talked about ultrasound, but I suspect it can help metabolism by increasing local tissue heat and thereby mimicking a healthy metabolism for a while. There are also heat-independant effects, possibly through structuring the cellular water a la Gilbert Ling.
We're going dark Peat right away. But bear with me.
1.Ultrasound on balls.
This is only in vitro. But very impressive.
Ultrasound Increases Testosterone production in leydig cells by up to 80% .
Doubled StAR, the rate limiting enzyme for steroid production .
https://pubmed.ncbi.nlm.nih.gov/36613865/

Here's a rodent study showing 20 min/day for 7 days increased testosterone by 62%
1.5-MHz frequency, 1-KHz repetition pulse rate, 200-microseconds pulse width, 30-V peak-to-peak amplitude and 20-mW/cm2 intensity) applied to the skin for 20 min/day for 7 days
https://pubmed.ncbi.nlm.nih.gov/1823286/
Someone filed a patent for using ultrasound for testosterone enhancement in humans. Including protocols and safe dosages.
https://patents.google.com/patent/WO2022026607A1/en?oq=WO2022026607A1
2.Anti-septic (200 mW/cm2, 0.37 MHz, 20% duty cycle and 20 min)
They induced sepsis in mice.
After 5 days all of the mice were dead.
In the sepsis + ultrasound group half of the mice were still alive after 5 days. Not only that, they seemed to recover from sepsis and were still alive after 40 days!

https://www.umbjournal.org/article/S0301-5629(23)00093-5/fulltext
3.Ultrasound increases topical absorptionof substances.
Aspirins absorption was enhanced by a factor of 300 ! Topical aspirin anyone ?
Ultrasound also enhanced steroid absorption. I'm thinking Idealabs + ultrasound.
This might be useful for topical hair loss formulas like as well, since absorption can be an issue here.
https://pubmed.ncbi.nlm.nih.gov/8692734/
4.Other:
Ultrasound helps with Inflammatory bowel disease.
https://www.researchgate.net/publication/348880743_Non-invasive_peripheral_focused_ultrasound_neuromodulation_of_the_celiac_plexus_ameliorates_symptoms_in_a_rat_model_of_inflammatory_bowel_disease
Helps with osteoarthritis.
"Long-duration low-intensity ultrasound significantly reduced pain and improved joint function in patients with moderate to severe osteoarthritis knee pain."
https://pubmed.ncbi.nlm.nih.gov/30326947/
"Scientific evidence supports the use of LITUS to treat soft tissue injuries, and improve outcomes for musculoskeletal injuries and post-operative recovery."
https://pubmed.ncbi.nlm.nih.gov/30198009/