Zhang Yanhang had read many such anecdotes: for instance, soldiers becoming unable to sleep due to the war, remaining awake for seven days and nights straight, and afterward losing the ability to sleep completely, requiring only a brief rest with eyes closed to sustain activity throughout the day.
While losing the ability to sleep might seem like a blessing, giving one eight extra hours of leisure time daily, it wasn't quite pleasant for the body. After all, sleep is meant to relieve the physical strain caused by exercise.
Once this vital process is lost, humans function like continually overheated machinery that can't shut down for cooling, ultimately breaking down far before reaching their expected life span.
