Old school: Quarterback Philip Rivers and Chargers visit Patriots to face the master, Tom Brady

Tom Brady’s unarguably handsome face fills the cover of his new book. It has a sharply designed logo — “TB12” — combining his initials and the number he wears on his New England Patriots jersey.

The book — “The TB12 Method: How to achieve a lifetime of sustained peak performance” — is a well-intentioned manual preaching the gospel of alternative exercises and diet, the stuff that’s made Brady a champion and a star into his 40s.

Keep your muscles soft and able to absorb punishment. Eat organically. Stay away from processed sugars.

It’s good advice. And it’s a New York Times bestseller.

It’s also very different from the PR17 method.

Philip Rivers, the Chargers’ quarterback, has a different approach to longevity and peak performance. And he’s not going vegan or anything to pull it off.

“Probably not,” Rivers said with a chuckle. “I may just try to reach down and touch my toes once or twice or every once in a while. I haven’t stretched much in 15 years, so I’ll start with a toe-touch.”

It turns out this isn’t his genuine “Aw, shucks” charm. He doesn’t like to stretch. He doesn’t really touch his toes. That’s all too new-agey for him.

“He never stretches,” tight end Antonio Gates said with a laugh.

The Chargers, in fact, have made it a point to make sure their star quarterback approaches aging with a more flexible mind — and tendons.

“I’m a little hardheaded in how old school I’ve always been in my approach to things, from workouts to lifting weights to cardio,” Rivers admitted. “But I’m starting to see the little things now, things you’ve been a little lax on.”

On Sunday, when the Chargers meet the Patriots, Brady and Rivers will have gotten there with vastly different approaches. But whether using the TB12 method or the PR17 cowboy boots method, the two players have defined their teams for more than a decade.

Some might say this game is as much Brady vs. Rivers as it is Patriots vs. Chargers.

“I don’t try to shy away from that,” Rivers said. “I don’t feel like I’m playing Tom Brady, by any means, but it’s still a big deal to me, as a fan of quarterbacks. All those times getting to go against Peyton Manning, I’ve still allowed myself to be that fan, in a sense — to have that love for the game, that love for the position. That’s what I grew up with. “When you’re going against a guy who has won all these Super Bowls and is still playing at the level he’s playing at 40, and he will be in that discussion that will never be answered, of who’s the best ever, to be a chance to be the QB on the other team, to me, it is a big deal.

“It’s pretty special.”

It’s pretty remarkable that the two players with 472 games of combined experience are still playing well this deep into their careers, with Rivers turning 37 before the end of the season and Brady at 40.

It’s a testament to their methods — however creative or old school. It’s a testament to their skills. And it’s a testament to an evolving NFL, which has had changes in offensive philosophy and rules that reduce hits to the quarterbacks.

“I definitely believe nutrition and the way these guys work has definitely contributed to their longevity, and I give the league tremendous credit,” Chargers offensive coordinator Ken Whisenhunt said. “One of the big things they’ve made an emphasis on his protecting those guys, the quarterbacks. It’s such an important position. It doesn’t underscore the fact that these guys are tough.”

Changes in offensive philosophies — quicker routes and faster throws — also have played a factor.

“Where the passing game has gone has helped,” Rivers said. “There’s so much more now where the ball is out of our hand a lot quicker, and we’re still able to move the ball and get chunk plays. We’re not back there with two-man routes all the time, having to wait and getting hit in the face waiting for guys to get open. Empty formations weren’t as popular 20 years ago. Now, we’re empty, and guys are dink-dink-dink all over the place.”

A quarter of the league’s starting quarterbacks were drafted by 2005.

“It’s great for our game,” Whisenhunt said.

Whether it’s stretching or lifting weights, eating steaks or grilling mushroom caps, Rivers knows whatever method he uses to stay on the field will always be tied to production.

“The guys you’re talking about, Drew [Brees], Peyton [Manning], Brady, you’re talking about the best ever,” Rivers said. “I still think it’s unique and rare. How smart they are, how accurate they are, all that plays a factor.

“I’ve never said I want to play until this day, or this many years. But as I stand now, the passion and love to compete I still have, from that standpoint, yes, if I can continue to play well enough, [I want] to play until I’m 40. It’s not something you’re just given. You have to go out there and prove it.”

dan.woike@latimes.com

Twitter: @DanWoikeSports