Fortunately, early the next morning, He Xiaoyao recovered completely. It seemed this method wouldn't work.
Running the Five Elements Formation in reverse could indeed prevent Heaven and Earth Spiritual Qi from entering a cultivator's body, but it would also cause harm.
Later, He Xiaoyao found a separate small room, set up the Five Elements Formation on its roof, and activated it in reverse while attempting to practice his cultivation inside.
Chapter 112