SPARTANBURG, S.C. (AP) -- Mike Tolbert is always ready for a good fight - even during the NFL offseason.
The Panthers feisty fullback spent his downtime in a familiar setting: a sweaty boxing gym in San Diego sparring with some aspiring professional heavyweight boxers and stepping up his conditioning workouts with his trainer.
The result: the squatty 5-foot-9 Tolbert lost 13 pounds of unwanted weight to get down to 250, which he says left him faster, quicker and better conditioned than last season.
Tolbert is coming off his first Pro Bowl season and the man teammates refer to as ''the bowling ball'' is eager to make sure his play doesn't slip entering his seventh NFL season.
''It's tough, but the strong survive - and I have to be ready,'' Tolbert said of the workouts.
Tolbert started boxing five summers ago in San Diego while playing for the Chargers as part of a program his trainer Dale Soliven called ''cross box.'' Soliven said Tolbert couldn't get enough of it.
The two have been working together ever since.
Soliven said after watching Tolbert move in the ring he's confident he could make it as a boxer if he wanted.
He said Tolbert recently stepped into a ring to spar with a young boxer who was preparing for his first professional fight.
''Mike was just destroying the guy. His hand speed is unreal,'' Soliven said. ''I had to pull Mike out of the ring and say, 'That's enough.'''
Tolbert said boxing suits his personality.
''It's man on man,'' Tolbert said. ''It's the ultimate sport of either you win or I win. That takes a lot of intensity. Everybody knows the mentality I have is that I will never let the man across from me beat me.''
Soliven said Tolbert is the most dedicated athlete he's been around.
When Tolbert was at the Pro Bowl last January in Hawaii he called Soliven saying he needed to get into the gym to work out as soon as he hit the mainland.
''I was like, 'Mike don't you want to take a couple weeks off?'' Soliven said. ''And he was like, 'No, this Pro Bowl thing has already put me behind on my training.'''
So Tolbert returned to the House of Boxing in San Diego the day after the Pro Bowl to spend time working to get into shape and shedding his goal of 10 pounds.
He's done that and more.
Tolbert, entering his seventh NFL season, said he's never felt in better shape in his life following the program Soliven put him through this offseason.
''The extra weight was a hindrance in the past,'' Tolbert said. ''I took it off the right way. It's definitely helping me. ''My cardio is beyond whatever I can comprehend,'' Tolbert said. ''Because we did so much road work and sparring and cardio, I feel like I can run for days. And you usually don't see short, fat guys that can do that.''
Soliven said the focus this offseason was conditioning, which included running diagonal sprints up a hill they call the ''Green Monster,'' stop-and-go movements and resistance band training.
But Tolbert's favorite part is stepping in the ring to spar.
He jokingly compares his boxing style to a mix between Mike Tyson and Floyd Mayweather and said he could probably beat anybody in the Panthers locker room in a boxing match with the possible exception of 6-foot-7, 330-pound offensive tackle Byron Bell, who was a high school Golden Gloves boxer.
Bell chuckled at the potential challenge, saying ''if he thought he was going to get in (for a punch) I would touch him on his chin and he wouldn't know what hit him.''
Panthers coach Ron Rivera could care less about Tolbert's boxing potential.
He just wants his dominant fullback in the best shape possible. But Rivera cautioned that he doesn't want Tolbert to lose too much weight.
He said Tolbert's power and girth, combined with his low center of gravity, is what helped him run for 361 yards and five touchdowns last season and help the Panthers win the NFC South championship.
''I want Mike to be round,'' Rivera said with a smile.
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