During the summer, one should go to bed late and rise early being sure to spend a good bit of time out of doors. In the fall, one should go to bed early and get up early, and during the winter one should go to bed early and get up late. Whether or not this theory is scientific requires further investigation. Nonetheless, during the spring and summer when all things are growing and the weather is warm and nice, it is certainly healthy for us to take a walk in the sun and inhale the fresh air outdoors. During the autumn, the sky is high, the air is clear, and the weather is comfortable.
Daylight grows less and the night is longer each day.
So it is also healthy for the body to take a walk outdoors and inhale the fresh air. Because it is so cold during winter, we should avoid chilly mornings and wait for the warm sunshine in order to prevent attacks of cold evils. According to foreign studies, early risers indeed do enjoy longer life. That is the time when all the birds wake. Chinese medicine recommends that everyone get up early during the spring, summer, and fall and wake up late during the winter.