The NFC North side, who play at Wembley Stadium this Sunday, have rushed for 362 yards so far this season.
The running back, who was named the league's MVP last season, told The AP: "We've just got to keep going, to keep grinding, to keep pounding. I have faith that our running game is going to open up and explode.
"People get the misconception that I'm trying to do too much. Every touch I want to get into the end zone. That's just me playing football.
"Now I can say there is some type of confidence I feel just knowing what type of guy he is, knowing his approach and his mentality. He's a guy I can count on. It feels good to have him back."
The Vikings face the Pittsburgh Steelers in London.