早睡早起 Sleep early and wake up early

If you watched the last episode of 秋香怒点唐伯虎 In the eye of the beholder, at the last episode, Tong Bak Fu 唐伯虎 advice to the emperor is to sleep early, wake up early 早睡早起. I agree with his explanation in the show. Wanted to know what his explanation is? Watch the last part in that last episode ;)