At least that's the way the team's longtime center Nick Hardwick describes it. Hardwick says opposing defenders shy away from contact when Mathews gets his legs churning.
"He is built like a block of granite," Hardwick said. "He is a pretty intense specimen, so when he gets going downhill, he is inflicting some pain on these linebackers and safeties."
Mathews' physical running style is something the rest of the offensive line feeds off of, according to rookie right tackle D.J. Fluker.
"I love blocking for Ryan," Fluker said. "Ryan just makes people look bad on the field. DB's don't want to hit him. They're scared of him because he's physical with them. It's great to see him have a great season. And it's been great to see someone go out there and give everything they have for their teammates."
In his fourth NFL season, Mathews has finally emerged from the immense shadow of being drafted as the replacement for LaDainian Tomlinson as the No. 12 overall selection in the 2010 draft.
The Fresno State product topped 1,000 rushing yards for the second time as a pro, rushing a career-high 236 times for 1,012 yards, averaging 4.3 yards per carry. Mathews has run for 415 yards after contact, which is No. 7 in the NFL.
"It's been good, really good," Mathews said after the Denver game last week, in which he ran for 127 yards. Mathews carried the ball 58 times in two games over four days.
"I'm sore, but that's what they are asking of me, so that's what I'm going to do. I'm just going to keep grinding, and doing whatever this team needs."
Added receiver Seyi Ajirotutu, who played with Mathews at Fresno State: "He's always been tough. But there's just something about this year that has been special. He's running hard, and everyone can see it. He just looks like a different back, and obviously he's running confident."
Mathews has stayed healthy, and is on track to play a full, 16-game season for the first time as a pro. And he's avoided putting the ball on the ground. Heading into the 2013 season, Mathews had fumbled 12 times, losing seven of them through three seasons. But this year, Mathews has fumbled just twice, losing one of them.
But more than anything, at 26-years old Mathews has shown maturity. He's done a better job of taking care of his body, preparing himself for the rigors of an NFL season with a rigid regimen before the season started, one which included reporting to training camp at the appropriate weight on his 6-foot, 220-pound frame.
"He puts a lot of work in," fellow running back Ronnie Brown said. "There's a lot of stuff that's not seen. People give him a hard time. But he runs the ball hard. He prepares hard in the offseason. And he puts in the work that's necessary, and I don't think a lot of people see that, so it's not appreciated."
Chargers quarterback Philip Rivers said he first noticed a confident and decisive Mathews during offseason work by watching his feet. Rivers said Mathews benefitted from offensive coordinator Ken Whisenhunt streamlining the team's running playbook, focusing on a steady diet of inside and outside zone running plays.
"There have been less schematic things, which gives him a lot of reps at the run packages that we have," Rivers said. "He has been able to rep them over and over and over again, going all the way back to OTAs. As a runner, much like as a passer, if you run it five times you feel decent, but if we throw it 50 times over the offseason then you feel a lot better.
"It's the same way in the running game. If I run inside zone against every look they have 50 times throughout the offseason, I'm going to feel a heck of a lot better about it than if I get a lot of different ones. I think that is one thing I can see. I felt confidence in his feet, confidence in his vision grow over this whole offseason throughout training camp and all year long."
While Rivers has shown the ability to pick opponents apart through the air, Mathews provides the hammer in the run game, keeping defenses honest and closing out games by grinding out first downs to run the clock.
Once considered a good bet to leave town when his contract ends at the end of the 2014 season, Mathews has proved that he's a good fit long term for the Chargers.