"I told him in the event of a water landing it could be used as a flotation device," the Pro Bowl center and team's resident comedian said. "He didn't think that was funny, though."
All jokes aside, Newton showed no obvious limitations from the fractured ribs suffered in an August 22 exhibition at New England.
He threw, according to head coach Ron Rivera and teammates, well enough that there are few if any concerns for how effective he will be in Sunday's opener at Tampa Bay. He actually threw more than anybody expected.
There seemingly are few concerns about anything surrounding Newton these days as his teammates made him a team captain for the second straight year.
It made headlines a year ago when Newton was bestowed that honor for the first time in his three seasons. After consecutive losing seasons -- 6-10 and 7-9 -- there had been questions about his ability to lead.
Those ended after the first pick of the 2011 draft led Carolina to a 12-4 record and the NFC South title. Newton continued to show his leadership during the offseason the way he stayed around the team while recovering from surgery on his left ankle.
That he's playing through whatever soreness remains from the rib injury without complaint is no more surprising than him being named captain.
"Cam's a tough guy," said tight end Greg Olsen, named a captain along with Newton, Kalil, defensive end Charles Johnson and linebackers Luke Kuechly and Thomas Davis. "He's a big, strong dude. If there's one thing the team knows, if there is any way for him to be out there and play at a high level he will.
"So there's not a lot of concern for that guy for the rest of the team. He'll be out there. He'll be fine."
Newton returned to practice Monday for the first time since New England linebacker Jamie Collins stepped on his back at the end of a 7-yard scramble. He reassured his teammates he was there for them, slapping the hands of every player in the huddle before taking his first snap.
"Cam, he's a fighter, he's a leader," left tackle Byron Bell said. "Ain't nothing going to hold that guy back. He looked good out there throwing the ball, calling the plays like he never lost a step. We've just got to keep him upright and we should be fine."
That will be key. According to ESPN Stats & Information, Newton has been sacked, hit while throwing or hit while carrying the ball 467 times during his first three seasons. That's more than double the total for any other quarterback, with Houston's Ryan Fitzpatrick next closest at 230.
That Newton takes those hits and doesn't complain, that he doesn't plan to change his style and slide instead of diving head first for every yard he can get, is another reason he's a captain.
"For me, a leader is somebody who leads by example," Kalil said. "Since the day he's gotten here he's done a good job in his preparation and how important it is. We give him a hard time about his pouting from time to time, but that's a reflection of how important it is to him.
"And even then he's the best self critic of himself. His self evaluation is one of the best I've been around.
"Obviously, the success came last year. But for me, he's been that guy since Day 1 and he's proven it in how he's played and how he's grown as a player and a leader."
He gets no argument from Rivera. Asked if his quarterback is more convincing as a leader now than a year ago, he deadpanned, "He's convincing, period."