´It was narrated that Ibn Mas'ud said:` "The Prophet [SAW] used to seek refuge (with Allah) from five things: From miserliness, cowardice, reaching the age of second childhood, the tribulation of the heart and the torment of the grave."
Explanation & Benefits
Hafiz Muhammad Ameen
The apparent meaning is that by "the worst age" is meant the most contemptible age, as mentioned in the previous hadith. However, "the worst age" can also refer to an age of misguidance, whether it be the age of youth or old age.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 5448