Some offer up the upward life-breaths to downward life-breaths, and the down-ward life breaths to upward life breaths. Stopping up the motions of both the upward and downward life breaths some devote themselves to the restraint of the life-breath itself. Others, who take limited food, offer the life-breath to life-breath.
अपाने जुह्वति प्राणं प्राणेऽपानं तथापरे। प्राणापानगती रुद्ध्वा प्राणायामपरायणाः॥