i think william perry is the heaviest rb cause you can look it up on youtube under "the refridgerator man"
This is just a guess, but I think it could be Brandon Jacobs. He plays for the New York Giants and is 6'4'', 264 pounds.
Marucs Allen retired at 37
average weight of an nfl running back is about 215 pounds
Chris Johnson is the best running back in the NFL right now!
Marqueis Gray is the heaviest NFL quarterback ever. He weighs in at 240 pounds and plays for the Minnesota Vikings.
Jimbo Johnson was listed at 6'9 during the 1926 season
how long is a running back career