Three things set Bob Seger apart from other rock stars his age: He looks it (no need for a hairdresser to know for sure about this 66-year-old); he decided to tour without releasing a new album (he's working on one but may never finish it), and he's not afraid to discuss retirement.

Is the 27-concert trek that brings him to St. Paul's Xcel Energy Center on Thursday going to be his last tour?

"It could be," he said last month from his Michigan home. "I flip-flop. I think maybe we can go back again in the fall and then I'm so frigging tired. I don't know if I should risk my health for this anymore."

Seger sounds more noncommittal than coy or calculating. The Rock Hall of Famer, who took a decade off to spend with his two children, is also nearly ecstatic about how this current tour stacks up to his 2006 comeback trek.

"I honestly think this is a better tour than the last one," he volunteered. "I've challenged myself and took on some songs I didn't think I could sing anymore -- like 'Feels Like a Number' and 'Shining Brightly' -- and I've been able to do it. Heh-heh-heh. It's a little rowdier."

Seger and his Silver Bullet Band have rehearsed 38 songs and typically play about two dozen each night, including "Old Time Rock 'n' Roll" and "Night Moves." Not on the list are "Still the Same" ("It's light," he says) and "Like a Rock" ("We have enough ballads").

No matter the set list, Seger is enjoying himself immensely. "I'm surprised at myself. It is very physically challenging, but I didn't think it would be this much fun," he said on a recent morning after sending his kids off to high school. "The body is holding up good." But he's had some vocal problems because of a cold that was hard to shake. Plus, it took some time to find his comfort level on the road again.

"Honestly, you worry -- at least I do, I'm kind of a worrier anyway," he said, sounding like he was confessing to Oprah Winfrey. "I was really tense in my shoulders and my neck. After a while, it settles in and you can do this. You get more confidence and you go out and you're able to go harder at it.

"Now my neck and shoulders don't hurt anymore. I've lost about 30 pounds, and I just feel a lot better. It's this violent exercise three times a week [in concert], and I'm working out a bit, doing situps and lifting weights, and it's all paying off. I've come down four pant sizes already."

Seger can get as confessional in conversation as he does in song. He doesn't shy away from the cigarette question. A 50-year smoker, he's cut back to "maybe less than a pack a day," he said. Translation: It takes him only about three songs to get his nicotine-stained voice warmed up in concert.

Then he breaks into a nervous raspy cackle -- and adds, "I'm smoking right now."

Recording tunes, new and old

Seger hadn't planned to tour. Instead, he was working in the studio, examining 40 to 50 unreleased songs from over the years. One was Tom Waits' "Downtown Train," which Seger cut in 1989 before Rod Stewart released a version. He decided to add female backup vocals and timpani, and released it as a single in February.

He had so much fun re-exploring these recordings with his musicians, Seger decided to practice with the band to see if a tour was feasible. "We rehearsed for like two months and said, 'OK, let's do it.'"

Actually, Seger is nearly halfway through a new album. He's completed a few originals, including "Hannah" (about his daughter Samantha), "Gypsy" and "I'll Remember You." But he's not promising a new album or even a boxed set (he dislikes them).

"This summer I will write, and when my voice comes back to full gear -- when I'm on tour some of the highs go, some of the lows go -- I'll try to go into the studio and finish a new album," said Seger, whose last two discs were released in 2006 ("Face the Promise") and 1995 ("It's a Mystery"). "Or if the writing gods are not with me, then we'll maybe do some new and some old [tunes] and put that out in the fall. But I hate to promise anything."

Seger just likes to write and record songs -- and spend time with his wife and two children. He says he worked nonstop in the 1970s and never had any meaningful relationships.

"I'd rather make music than tour," he said. But he admits: "Once you get into the tour, you give it your best shot. You respect the audience. Bruce Springsteen told me that years ago and it really stuck. You owe it to the people who have paid the money to go out there and play like it's the last time you'll ever get a chance to play."

Did he say "the last time"?

Actually, this limited tour was built around his son Cole's high school graduation May 27. "He's very adamant that he wants me there when he walks, and I will be there," Seger said.

He has a concert the next night in Grand Rapids, Mich. -- then nothing on the schedule. "I don't know if I'll go on from this leg [of the tour]. We'll see. I just change my mind. You want to go out on a high note if you can. Is it time to go away? Nobody ever goes away in this business, and maybe I'll be the one who does."

Jon Bream • 612-673-1719 Twitter: @jonbream