UFC: Five Fighters on the Rebound in 2012 (Yahoo! Contributor Network)

Everyone gets knocked down at some point in his or her life. The true judge of their character is how one responds to adversity.

This adage is played out most literally and brutally in the UFC's Octagon, where you get punched, kicked, kneed, and choked for your troubles on the way down.

But fans love redemption stories, and several mixed martial artists on the UFC roster are fighting their way back after undergoing tough stretches. Here are five fighters who sure look back on the rise in 2012:

Jake Shields put together an impressive win against Yoshihiro Akiyama earlier this year.
(Getty Images)

Jake Shields, welterweight: Few big-time fighters had a tougher go of things in 2011 than Shields. The former Strikeforce middleweight champion lost to Georges St. Pierre in the main event of UFC 129 in Toronto in front of 55,724, ending his 15-fight win streak. Then his father, Jack, passed away in the weeks leading up to his Sept. 17 bout with Jake Ellenberger. Shields stuck with the fight, but lost in a swift and vicious first-round TKO.

Shields, though, wasn't deterred. He took on the challenge of Yoshihiro Akiyama on Akiyama's Japanese home turf and put on his best performance in the UFC Octagon. Shields outpointed Akyiama in a compelling battle that's on the short list of the best fights of 2012 thus far. If that's a sign of what to come from the San Francisco native this year, then expect him to remain very much in the mix at 170 pounds.

Ryan Bader, light heavyweight: There's really no way to sugarcoat this: Bader's 2011 was mostly horrendous. The "Ultimate Fighter 8" champion entered the year in a semi-main event bout with Jon Jones at UFC 126. Given Jones' monster performance in 2011, this seems hard to believe in hindsight, but at the time, there was vigorous debate over who would win the fight. Bader was on the wrong end of a one-sided beatdown, getting finished in the second round. He followed the loss to Jones at UFC 132, when he was choked out by Tito Ortiz for Ortiz's first win over someone not named Ken Shamrock since 2006.

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Such high-profile losses have derailed the careers of many highly touted prospects, but Bader instead used the setbacks to retool his game. He closed 2011 with a quick knockout of Jason Brilz, and opened 2012 with his biggest career win to date, taking apart former UFC light heavyweight champion Quinton "Rampage" Jackson on Feb. 26, with 30-27 scores across the board.

Bader and his wife are expecting their first child next month, so you can't blame him for taking a break before lining up his next fight. But it's safe to say that when he returns, he'll do so with his status as one to watch fully restored and ready for another shot at a top name.

Anthony Pettis, lightweight: Pettis stands as the MMA world's proof that in today's corporate America, promises mean nothing if they're not on signed paper. Pettis went into 2011 as the toast of the MMA world, winning the WEC lightweight title from Benson Henderson on Dec. 18, 2010 in the main event of that company's final show, with his decision-sealing "Showtime kick" going viral in the process.

Pettis was promised the next UFC title shot after defeating Henderson. But then Frankie Edgar and Gray Maynard fought to a New Year's night draw in a title bout, which meant the rest of the division was iced, awaiting their October rematch. In the interim, Pettis lost a unanimous decision to Clay Guida, shoving the presumed title-challenger-in waiting further down the line.

But Pettis didn't let the letdowns keep him down. He got back into the win column at UFC 136 with a decision over Jeremy Stephens, then took out Joe Lauzon with a spectacular head kick at UFC 144. While a likely rematch between Edgar and new champ Henderson means Pettis will have to continue waiting for that elusive title shot, he's showing he'll uphold his end of the bargain while he waits for the promise to be fulfilled.

Ian McCall, flyweight: The fighter called "Uncle Creepy" is a testament to perseverance. He had two stints as an undersized bantamweight in the WEC and went 1-2, with his final bout a 2009 loss to current UFC champion Dominick Cruz. This would have caused a lot of fighters to give up on their dreams, and indeed, McCall fought only once over the next two years. But he dropped to 125 pounds in 2011 and dominated the competition in California's Tachi Palace Fights promotion, winning the flyweight title and earning his spot in the UFC.

McCall's return to the big time came on March 3 with his controversial draw against Demetrious Johnson in the flyweight tourney semifinals. The bout was incorrectly announced in the cage as a win for "Mighty Mouse." By the time the scoring error was discovered and the bout was declared a draw, it was too late to go to the planned fourth-round overtime. This was a shame for McCall, who dominated a fading Johnson in the third round. McCall will rematch Johnson (expected on the TUF Finale, but not yet announced), but regardless of the outcome, he's already marked as a fighter to reckon with at 125.

Cain Velasquez, heavyweight: Is it a bit of a reach to include Velasquez on this list? Perhaps. But the fact is, it has been a year and a half since Velasquez steamrolled Brock Lesnar to claim the UFC title. Since then, he spent a year on the shelf with a shoulder injury, and then lost his title in quick fashion to Junior dos Santos in November.

But Velasquez's path back to the top is clear. He'll face Frank Mir at the loaded UFC 146 in a bout that seems to favor him stylistically, so long as he can avoid Mir's submissions. A win there should set him up for a a shot at the winner of the UFC 146 main event of dos Santos vs. Alistair Overeem and a chance to put the past 18 months in his rear-view mirror.

Who's your pick for rebound fighter of 2012? Whether it's someone on this list or another fighter, leave me your thoughts in the comment section.

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