According to Ethan, Extreme Endless training refers to a process in which you use any kind of healing or divine magic to heal your body every time you finish your training routine.
As everyone knows, frequent training helps strengthen the body by creating micro-fractures in bones and micro-damage in the muscle fibers of the body and then letting the body rest and heal to strengthen them overall.
This way the body continuously goes through a cycle of stress, repair, and improvement over and over, making you slowly become stronger each time.
But this process is very slow, as your body will take longer and longer time intervals to heal itself the more you damage it and the more you break it.
But the 'Extreme Endless Training' method eliminates 'rest' and 'repair' factors from the usual training system.
By using divine power to heal or some other healing item to heal yourself, you can instantly recover from all the damage done to the body.
