EDEN PRAIRIE, Minn. (AP) - The first week after Adrian Peterson's reconstructive knee surgery was a grueling one.
The pain from the surgery was agonizing, and it prevented him from sleeping much most nights. That means there was plenty of time for the mental torture to take its toll as well, as the Minnesota Vikings star running back wondered what he could have done differently in that game against the Redskins to prevent such a devastating injury.
Now that Peterson is up walking around and has started the rehabilitation process, he is determined to return to his All-Pro form.
Peterson and Vikings head athletic trainer Eric Sugarman met with reporters on Friday to give an update on his recovery, two weeks after Peterson had surgery to reconstruct the ACL and repair the MCL in his left knee.
"I feel like the first week was the toughest part for me, not being able to sleep, waking up every two hours, just dealing with the pain and the frustration, looking ahead like, `Wow, I've got a long way before I'm able just to move around and walk,"' Peterson said. "But after that first week, I feel like things really just started to calm down. The pain started to subside. I was able to just get more motivated about the process."
Peterson injured his knee at Washington on Dec. 24. It was the final blow in an excruciating season for the Vikings (3-13), who tied for the worst record in the franchise's 51-year history. Dr. James Andrews performed the surgery on Dec. 30, replacing his ACL with the patellar tendon.
Peterson ditched the crutches and has started to work on range-of-motion exercises and rebuilding strength in his quadriceps muscle. The Vikings have assembled a regimented program for him in hopes of having him ready for his previously stated goal of Week 1 next season.
"His surgery was certainly a success and everything's fine," Sugarman said. "That's the one thing that you really have to be cautious the first couple months. You can't push him too hard, otherwise you can put him at risk. He knows that. We all know that. That's why the protocol is setup the way it is."
Peterson will perform the rehab both in Minnesota and at his offseason home in Houston. He knows that it's going to be a difficult process, but that hasn't shaken his confidence.
"I know that anything I put my mind to, I'll be able to accomplish," he said. "I feel like I'm going to come back better than before.
"I know people might laugh at that or think otherwise, but you know what? It doesn't matter what they think or how they feel about it. The only thing that matters is how I feel about it and what I believe."
The bar to return to is certainly set pretty high. Peterson has been the most dynamic running back in the league since coming in as a rookie in 2007. He rushed for 970 yards and 12 touchdowns this season before being injured and signed the richest contract for a running back in league history before the year began.
"No one's going to work harder than this guy," Sugarman said. "So, the hardest part for me is going to be keeping him in check and he's got to follow the protocol and not try to do too much, not be influenced by other people and just do it. He'll do fine."
Follow Jon Krawczynski on Twitter: http://www.twitter.com/APkrawczynski.