Adrian Peterson believes he can still dominate at age 31, but the running back admitted that the toll his body has taken will be what leads him to walk away from football.

"That's it," Peterson said. "Training camp, going through the grind, OTAs and all that -- that will definitely be the deciding factor. Physically, body-wise, I'll be good. It's just mentally -- like with OTAs, I'm out there practicing, I'm going, I'm putting in work. But it's so repetitive that it's more suited toward the young guys and getting them into the system. It gets kind of boring."

Peterson needs 6,681 yards to break Emmitt Smith's all-time rushing record.