Sizemore is currently recovering from a procedure on his lower back.
"I still feel like I'm pretty young," Sizemore said on Tuesday. "I love this game and I don't see myself calling it quits anytime soon."
Sizemore has done most of his training of late away from the public eye, but the sidelined center fielder held court with reporters at his locker prior to Tuesday's game against the White Sox. In the early afternoon hours, Sizemore went through some running and agility drills in left field at Progressive Field after throwing in a long-toss session.
Due to being on the 60-day disabled list, the 29-year-old Sizemore is not eligible to be activated until June 3 at the earliest. If he can continue to make steady progress, Sizemore said he plans on doing everything in his power to be ready to officially rejoin the Indians at some point in early or mid-June.
"We're still shooting probably for some time in June," Sizemore said. "We'll go from there. I don't know if anything is set in stone yet. It all depends on just how the body responds and where I'm at with each progression."
Sizemore said he has started to hit baseballs off a tee and he should gain clearance to begin hitting in soft-toss sessions and then batting practice during the team's next homestand, which begins on May 16. That will be a big step for Sizemore, who underwent a microdiscectomy operation to repair a herniated disk on March 1.
The center fielder indicated that his back feels fine, noting that it was the feeling in his left leg that was most affected. While working his way back from that surgery, Sizemore is also rehabbing the right knee that he injured last season. He does not want to return to the Tribe until he is as close to 100 percent as possible.
"I still have a long ways to go," Sizemore said. "I have a lot of work to do, but I feel like I'm at the tail end of this rehab."
Indians manager Manny Acta said it is a good feeling to know that Sizemore could be rejoining a team that is battling for the American League Central title.
"It's encouraging that we're playing good baseball right now," Acta said. "It gives a guy an opportunity to just rehab and then for him to come back into a good stuation, instead of us not playing well and having to just be hoping that the guy is ready as quick as possible to maybe come in and be the savior.
"That's not the case right now. Guys are playing well, so, hopefully, we'll continue to play well and, when Grady comes in, we're in a good spot. If he can give us a lift like he's capable of, that's good. That's a plus."