I didn’t post the link to the Inigo podcast but here are some references:
At the time that podcast was first posted (in another thread) I commented that there was as much pathology as there was performance in the podcast. There’s not a lot of discussion on that podcast regarding what kind of training induces what kind of changes to mitochondria.
That thread is here:
@bbarrera also linked a few articles by Inigo in that thread.