In the NFL these days concussions aren't taken lightly. Carlos Dunlap knew that. So he understands why his extended sedentary state on the sidelines this preseason occurred.

That doesn't mean he likes it.

Dunlap suffered a concussion July 31 and eased back into individual work Monday it was the first physical activity he's been allowed since enduring the injury.

“It's frustrating” Dunlap said. “Physically I feel I can still run lift weights whatever. But it's not in my best interests right now. It's like a mind game now.”

Not to mention a game of deja vu. The fourth-year pro is yet to manage a preseason without missing games. Of the 15 preseason games since being drafted in 2010 Dunlap only participated in four. He missed the entire preseason in 2011 and started the first game last before suffering a knee injury in the first quarter and sitting out until Week 3 of the regular season.

The primary difference would be this year he's not able to go through a physical rehab process or continue working out with healthy muscle groups. For three weeks he stood on the sidelines and watched. The injury keeps his legs fresh but does deliver a hit to his strength when the season starts in Chicago.

“My legs will be fine” said Dunlap who also suffered a concussion in 2010. “I'll be able to run past people. I might not be able to blow them up but I'm going to run past those guys.”

Dunlap signed a five-year extension worth $40 million this offseason and contributed 20 sacks in his first 38 games. He recorded six sacks and forced four fumbles last season.

He will continue to take part in individual drills and see how he reacts to the physical exertion. As Dunlap passes those tests he'll be cleared for full contact. Marvin Lewis indicated Dunlap appears to be on track for a return but with concussions these days you never can be completely sure.

“Obviously those are touchy things” Lewis said. “It was good to see him. He was out (Tuesday) morning participated. Hopefully we continue to move forward.”