It's not surprising Minnesota Vikings head coach Mike Zimmer is already looking to temper expectations for his team next season. The return of running back Adrian Peterson, the addition of Mike Wallace and the drafting of Trae Waynes and Eric Kendricks have optimism running rampant in and around Minnesota and even has some, including we here at HNGN, thinking playoffs for the Vikings. Still, while Zimmer might not yet be ready to crown his team or make any major, even semi-boastful statements, Peterson isn't.

Shortly after indicating that he keeps Emmitt Smith's NFL-record single-season rushing total as his preseason expectation and that he believes 2,500-yards is possible, Peterson, set to enter his age 30 season, suggested that he doesn't expect to be slowed by wear and tear anytime soon.

"I don't see the end," Peterson said Sunday, via Peter King of Sports Illustrated. "Straight up and honest with you, I feel like, and I don't know if I'll do this, because I feel like once my mind tells me, You know what-I'm not loving this game anymore, I'll walk away whenever that time is. But I honestly feel I can play this game until I am 36 or 37 years old. And at a high level."

While this would seem a ridiculous claim if it came from most any other NFL running back, Peterson, as he has proven time and again, is not just any running back. In most of seven NFL seasons and on game of an eighth he's amassed 10,190 yards and 86 touchdowns rushing. He's added 208 receptions for 1,715 yards and five touchdowns. Peterson currently sits at No. 28 on the NFL's All-Time Rushing Leaders list. With a good season in 2015, he could vault himself into the top-20 or, with a particularly good year, even the top-15.

Considering the team recently restructured his deal, guaranteeing more money and leaving both sides an out after three seasons, it seems the Vikings are banking on his remaining at a high level of production at least until then.

Of course, the history of running backs positing major output past age 30 isn't great. Former Giants running back Tiki Barber managed two seasons of over 1,600 yards rushing in his age 30 and 31 seasons. Ricky Williams, after his return to the game, managed a 1,121 yard season at age 32, and Smith, the league's all-time leader, managed seasons of 1,021 yards (age 32), 975 yards (age 33) and 937 yards ( age 35). Marcus Allen is the older player to even approach the 1,000-yard mark; in 1996 he rushed for 830 yards as a member of the Kansas City Chiefs at age 36.

In short, Peterson will have to buck serious and consistent NFL trends if he's going to play well into his 30's, meaning it's highly unlikely he could actually pull it off.

Then again, if there's any player that could do it, it's certainly the uber-athletic Peterson, the guy who came back from a torn ACL to perform at a high level months faster than anyone rightfully expected.