When energy and vitality were linked, it would form a small cycle within one's body. From then on, True Energy would automatically circulate at any time and place. There was no need to deliberately circulate it.
For those below the Acquired Stage, when cultivating, they would need to purposely direct their True Energy. However, for Acquired Stage experts, even while they were not training, their True Energy would still circulate continuously. It was equivalent to their cultivation increasing at every moment.
Although it was not as fast as when they were cultivating, it was equivalent to cultivating non-stop at every moment. The speed of their improvement could not be compared to those below the Acquired Stage.