Asked if he's always been a patient person if a mellow gene had been passed down by his parents Marcus Lattimore laughed.

No it's quite the opposite the 49ers running back said this week.

Patience was very much an acquired trait. And it didn't come easily.

"It's something where I had to really train myself to be that way" he said. "It took awhile. It's something I had to grow into. Because it's not there naturally."

For the past six months Lattimore had been rehabilitating alongside fellow injured draft picks Tank Carradine and Quinton Dial. On Tuesday Carradine Dial and two other rehab partners wide receiver Mario Manningham and cornerback Eric Wright joined the rest of the 49ers at practice for the first time this season.

Rehab is slow and repetitive. It's "Groundhog Day" at the gym. Every day is leg lifts leg curls and leg extensions. There are enough sessions on an exercise bike to make you feel like you've pedaled the Tour de France 20 times.

What makes it more tortuous is that just a few yards away the rest of the team practices and prepares for the upcoming game. An injured player must feel like a child banished to his bedroom face pressed against the window while the other kids play outside.

Players cope with their time on Monotony Island with humor and camaraderie.

Lattimore said you can't help but crack jokes and bond with the guy stuck on the exercise cycle next to you.

"We all relate to what we've all been through and what we're going through in the rehab" he said. "Those have become my brothers. I mean we jelled. And there's nothing that can take that away."

While his mates have escaped the island Lattimore remains stranded.

That's where the patience comes in. Lattimore 21 is the third-youngest player on the 49ers' roster but comes off as one of the most mature.

He said he had to be. Later this month is the one-year anniversary of the grisly knee injury that left players on two teams – Lattimore's South Carolina squad and visiting Tennessee – kneeling in concern as he was carted off the field.