DENVER (AP) -- Rod Smith insists he's still pretty hip even at age 37.
The 14th-year pro who holds all of Denver's career receiving marks said Thursday that his bum left hip -- and not age -- caused him to lose a step last season.
He also revealed that the hip, which he had surgically repaired in February, had been bothering him since 2004, the year before he earned his third trip to the Pro Bowl.
So, what finally pushed him under the knife?
"Last year I couldn't even sleep ... because my leg was throbbing all night," Smith said.
"So, basically, I stayed up the whole year last year and that's not good.
That's what makes you old, when you're not getting any rest and you've got to go out here and fight with these young dudes.
"That's what gets you run out of the league real quick."
Smith said his hip was such a mess -- torn labrum, frayed cartilage, bone spurs, floating fragments -- that his surgeon couldn't believe he had played at all last season.
"And I'm just like, I feel I'm tougher than most people," Smith said.
"Pain to me is secondary.
If I can get through it for three hours on Sundays, I'm going to give these guys all three hours of everything I got.
I did that.
And at the same time I beat myself up in the process."
Smith said he hopes to be ready by training camp in two months but won't run any routes until he's 100 percent.
He was in sweats and on the sidelines for the Broncos' passing camp Thursday, enjoying the respite even though second-year pro Brandon Marshall is making strides toward unseating him for the starting job opposite Javon Walker.
Marshall's emergence late last season and Smith's slide -- his 52 catches for 512 yards and three TDs represented his worst season since becoming a starter in 1997 -- lead many to believe Smith's starting days are already over.
Smith isn't among them. He said that once his hip is healed, he'll return to his old form.
"The only way I'm going to go on the football field is if I'm healthy.
And if I go on the football field and I'm healthy, I expect to do the same things I did in 2005.
Not 2006, but what I did in 2005 was good enough to get us to the AFC championship game and it got myself in the Pro Bowl, so I expect to get to that level again," he said.
"But at the same time I've got to be smart ... because I put myself through a lot of strain individually to try to do what's best for our team and it might have hurt me."
Smith, who kept his hip problem a secret until the offseason, said he never felt good in 2006.
"Honestly, it never was more than 100 percent during any game in the whole year," he said.
"But it's no excuse ... because if I'm out there, my thing is to make plays.
"But at the same time, I realized how much it limited me after I went back and looked at it.
And I said I can't do that to myself again, because it's putting way too much strain on my body to try to make the routine plays that I was used to making; it made things a lot harder."
Smith ditched his crutches about 10 days ago and is riding a stationary bike and doing elliptical work while his teammates go through practices.
Retirement isn't something that's crossed Smith's mind.
"If you can be productive, that's what the coaches want, and if I'm not productive, trust me, the coaches don't have to fire me.
I'm going to leave on my own," Smith said.
"But I honestly feel that I can be productive, and that's the only reason why I'll go back out there."
Ever since joining the team as an undrafted free agent in 1994, Smith has never missed a single day of the team's offseason strength and conditioning program. He insists his mark is still intact.
"I am gaining strength and I am conditioning," he said.
"I lift. I run every day. And I'm Aquaman. I swim every single day. Trust me. It all counts."
(Copyright 2007 The Associated Press. All Rights Reserved)