The power of deception
The exercises involved strengthening the diaphragm, in ways that were very similar to exercising the rest of the body. Muscles were generally trained and strengthened by expanding and contracting them against resistance, usually a weight load. One would shift weights by expanding and contracting particular muscle groups across the body, leading to them growing stronger over time.
The diaphragm was no different in this regard. Rui spent a lot of time inhaling and exhaling through a breathing contraption that severely hindered breathing, this meant the user had to push his diaphragm to the absolute limit if he or she wanted to breathe normally.
As Rui gasped and wheezed during this exercise, for the very first time in his second life, he came to hate a training regime.