By the concentrated practice of Kriya Yoga pranayama—offering the inhaling breath into the exhaling breath (prana into apana) and offering the exhaling breath into the inhaling breath (apana into prana) —the yogi neutralizes these two life currents and their resulting mutations of decay and growth, the causative agents of breath and heart action and concomitant body consciousness. By recharging the blood and cells with life energy that has been distilled from breath and reinforced with the pure spiritualized life force in the spine and brain, the Kriya Yogi stops bodily decay, thereby quieting the breath and heart by rendering their purifying actions unnecessary. The yogi thus attains conscious life-force control.