Cardinals quarterback Carson Palmer said his arm feels so good he could throw 150 passes in practice -- but he won't.

Quarterbacking has been Carson Palmer's life for so long, the inherent reality of the position – that the team's fortunes ultimately rise and fall depending on its play – is also just part of life.

"That's how you kind of grow up in the position," Palmer said. "You're probably a little nervous at first as you're coming up, but then you get kind of addicted to it and enjoy it and enjoy the pressure that comes with the position."

As the Cardinals held their first practice of training camp Saturday, Palmer's 15th season again holds a predictable place. He is the linchpin of what the Cardinals will do.

There are other factors, of course. On offense alone, the Cardinals need the line to hold up better than it did last season, and the wide receivers must play better as a group. But if Palmer stumbles, the outlook will darken quickly.

"I've been fortunate enough to be around some really good (quarterbacks)," coach Bruce Arians said. "Always fun going to practice and going to the stadium Sunday when you have a good one. When you don't have a good one, it's rough."

The Cardinals had a little bit of both in 2016.

[READ: NO PALMER OR FITZGERALD IN HALL OF FAME GAME]

Palmer was not able to repeat his fantastic 2015 season. Some of that came down to factors outside his control, like the injuries that shredded some of his key offensive components (along with Michael Floyd's struggles).

"It was just a trying year," Palmer said.

But Palmer didn't play like he was capable either. He didn't throw an interception until the fourth quarter of the third game at Buffalo, but he was picked off four times in that quarter, and first half of his season was derailed quickly.

It was slowly revealed that Palmer had a sore arm. Palmer acknowledges now he could tell – "This game, it is so ingrained in you, you fight through it, fight through it, fight through it (but) no doubt, you notice it," he said – but it

became a focal point this offseason as he and the Cardinals planned to prepare him better at age 37.

Not only will he continue to take Wednesday practices off during the season, something started last year, but he cut way down on his throwing this year. The goal isn't to get Palmer back to his MVP-type numbers of 2015. Arians has a more reachable goal.

"To play like he did in November and December," Arians said. "If he plays that well we should be a good team."

Despite his age, Palmer said he doesn't feel old. To the contrary, after throwing "a lot more" from March to the beginning of camp in 2016 than he did this year, his arm and his confidence are both 100 percent.

"It's hard to explain, just feel better," Palmer said of his arm. "You feel like you could throw 150 balls in practice, which I am not going to do."

There is no talk of retirement. Palmer said he doesn't know how much longer he'll want to play. He just knows that, besides feeling good, he remains excited for camp – another element usually missing from a guy near the end.

That's a good sign coming from a player who is the key to the Cardinals.

"At the end of the day, this league is a quarterback-driven league," center A.Q. Shipley said. "I think people see that. You lose your guy, it's like, people are looking around, 'What do we do now?'

"We're fortunate we have an awesome backup in Drew (Stanton), but a lot of teams aren't afforded that. With Carson, everyone realizes what we have and we all have the full trust in him."