Back in September, former NFL great Herschel Walker announced that he was taking on a new career: mixed martial arts. At age 47, Walker signed a deal with MMA league Strikeforce and began training for his first fight. Now that first fight will go down on January 30th on Showtime. His opponent has yet to be announced, but Walker says he's ready to throw hands.

"I wouldn't have gotten in to this if I didn't know I could do it," Walker, who has a fifth-degree black belt in tae kwon do, recently told the San Jose's Mercury News. "I can fight."

Walker says he's in great shape and will be able to compete with younger fighters in the league. He even thinks he can go back to the NFL.

"I could still play football today," Walker said. "Now I couldn't take every snap. I've slowed down a little bit, but I'm still faster than 80 percent of the guys in the league. That's why I know I can step in to the cage."

Walker also added that he's not in this for the money, but wants to keep competing in some form. He's donating the money he earns from the upcoming fight to charity.