Is "LIMIT 1" recommended for query where WHERE condition is based on PK?

I am querying a mySQL database to retrieve the data from 1 particular row. I'm using the table primary key as the WHERE constraint parameter.

E.g.

SELECT name FROM users WHERE userid = 4

The userid column is the primary key of the table. Is it good practice to use LIMIT 1 on the end of that mySQL statement? Or are there any speed benefits?