HOUSTON -- When Adrian Peterson's trainer, James Cooper, says he treats Peterson like a fighter getting ready for a big bout, he's speaking metaphorically.

Mostly.

Cooper's background in boxing and mixed martial arts has led Peterson, the Minnesota Vikings' star running back, to incorporate some of it into his own training. MMA, in particular, has become a popular workout option for a number of NFL players, and a significant part of Vikings defensive end Danielle Hunter's offseason regimen has included boxing at Peterson's O Athletik gym in Houston.

Adrian Peterson, practicing with fellow running back Matt Asiata, has incorporated some boxing and some MMA into his workouts. AP Photo/Jim Mone

For Peterson, sparring in a ring brings some direct benefits when it comes to carrying a football on Sundays.

"[It helps with] being patient," he said. "[It's] being patient and always having your guard up and always being prepared and ready for that attack. You get in the ring and you get sloppy, you start to swing too much, and you're gonna get knocked out before you know it. By being patient and having a defensive mindset, you always have your guard up."

Peterson said he has done more training with boxing than MMA, but he has tried some MMA because Cooper has suggested it.

"It's fun, man," he said. "It’s good for keeping the body flexible, for endurance as well, and hitting those fine-tuned muscles that you don't know you have. Just within that [first] 20-30 seconds you're going to be exhausted. You're going to realize, 'OK, it really takes a lot to be able to do this.' And then you get in the ring with someone that's experienced, and they are putting you in submission holds and locks and stuff. It takes it to a totally different level."

Before Bellator 149 took place at the Toyota Center in Houston on Feb. 19, O Athletik hosted several fighters for a workout and media day. Cooper's experience with the discipline means that MMA probably will continue to show up from time to time in Peterson's workouts, as Cooper continues to look for ways to keep Peterson on edge. The boxing ring, Cooper said, is one inspiration for Peterson's notoriously ruthless running style.

"With Adrian, we'll do things where we're working on how to hit a guy, somewhat like boxing," Cooper said. "The reason we box like that and spar is to teach him how to be combative with a defensive lineman -- sometimes, hit him in the mouth, and the next play, go right at him, but then take a step over to the side as you go right at him. They're going to brace for that load, and then you can make your move. And then, after that, make a double-move stutter and hit them right in the mouth. It's several things that he can feel and understand. It gives him the mentality of how to be a true warrior on the fly."