NASHVILLE, Tenn. — The corridors of Vanderbilt’s football facility began buzzing a little past noon Thursday, right when Dallas Clark addressed a meeting room packed with about 90 fellow current and former NFL tight ends.

The 43-year-old former All-Pro, who won a Super Bowl with the Colts and last played in the 2013 season, was about to take the practice field again. Clark would knife through passing routes alongside his younger cohorts. He’d look fast enough under the Tennessee summer sun to lace up his cleats for another NFL game — at least for a few snaps.

But first, Clark would deliver a message that epitomized the tight end experience, and that grabbed everyone’s attention. Capturing that spirit is a central goal of Tight End University, a summer convention launched by 49ers star George Kittle last year that has quickly ballooned into the largest positional summit of its kind.

“I get excited talking about this game,” Clark said. “And being in a room with those men, it’s hard for me to just ho-hum it and go through the motions. I just got fired up. We can talk until we’re blue in the face, but it’s got to come from the heart. It’s a mindset.

“And then to be around the best of the best, are you kidding me? How do you not get fired up?”

Kittle and Kansas City’s Travis Kelce, the game’s two highest-paid tight ends, were indeed ebullient about the convergence, which ran from Wednesday to Friday this week.

Said Kittle of Clark: “He was talking about mindsets, flexibility, how to stay alive in the NFL for (11) years. A switch just kind of flipped and he had this passion. At the end of the day, when it’s third-and-5 and a ball is thrown, you have to have that killer mindset. ‘That’s my ball.’ The whole room just picked up. That’s just what football is. It’s passion. It’s desire for the game. It’s desire to be great. He definitely has that and he gave us all a little kick in the butt and it felt good.”

Said Kelce: “Hearing Dallas talk about his mentality, man. It’s cool to hear everyone’s story and how they view it. Because a lot of it is just reassurance. Reassurance that you know what you’re doing. That you’re a professional and on the right track to get better. And then taking a little bit of everything from guys around you. I appreciated Dallas sharing his love for the game and being a tight end.”

Then, when Clark took the field with Kittle and Kelce, scurrying through drills conducted by Greg Olsen — another former All-Pro tight end who recently retired and has assumed the role of Fox’s top game analyst (he’s scheduled to call the Super Bowl this season) — he again grabbed Kelce’s attention.

“Dude, you look like you play here,” the Chiefs star said to Clark.

Tight End U began in 2021 as the brainchild of Kittle, Kelce and Olsen. Kittle lives on a 75-acre property just outside of Nashville in the offseason and invites a handful of fellow tight ends to train with him inside a customized facility he has dubbed The Barn. He initially aimed for a two-day extension of those workouts, and about 35 tight ends showed up to the inaugural event last year.

This week, Tight End U welcomed about 90 players. It maintained 2021’s popular activities, such as a restorative yoga session taught by Kittle’s sister, Emma.

This 2022 installment also attracted a handful of corporate sponsorships and led a donation drive that, with the help of Bridgestone (whose American subsidiary is based in Nashville), raised over $681,000 for the Boys & Girls Clubs of America.

A shaved ice truck and water balloon fight between dozens of hulking NFL tight ends and several members of Nashville’s local chapter of the Boys & Girls Clubs capped Thursday’s session of on-field work.

“I think one of the great things about football, especially the NFL, it gives us this platform that kids want to be an NFL football player,” Kittle said. “Kids want to listen to football players. You have this platform to be able to give back. … All I want to do is have these kids have the opportunity to go out and play sports — whether it’s baseball, basketball, football, hockey — whatever it is, give them the opportunity to do these things. So they don’t have anything taken away from them. I just want kids to try everything and, with this money, hopefully they can.”

NFL interest this year was so great that Tight End U had to turn away some players, but Kittle said the goal is to accommodate up to 140 tight ends next year as the event continues to grow.

“I figured if you put George Kittle, Travis Kelce, Greg Olsen and Darren Waller in the same room, what NFL tight end is not going to want to be a part of that?” Kittle said. “We kind of bet on that, and look what happened.”

Three quarterbacks — the Bills’ Josh Allen, the Jets’ Zach Wilson and the Jaguars’ C.J. Beathard (a Nashville native who was previously Kittle’s teammate in college at Iowa and with the 49ers) — came to throw passes at the event. Last month, Kittle said the 49ers’ Trey Lance was also planning to be in attendance, but a reported scheduling conflict kept the second-year QB away.

Kittle was back and active on the field for the first time this offseason and was moving well. Kittle had attended the 49ers’ recent OTA practices and veteran minicamp sessions but didn’t participate as he allowed a lower-body injury to fully heal after a strenuous season.

Two large bears, the mascots of headlining sponsor Charmin, roamed the field on the hot afternoon. With temperatures soaring over 90 degrees, a four-person rotation worked the stuffy costumes in 15-minute shifts. One of the mascots even managed to hold on to a few tight spirals from Allen despite the severe movement restrictions the bulky costume presented.

When route-running drills commenced, Allen joked with Clark, asking whether his passes were easier to handle than the occasionally wobbly spirals thrown by retired Hall of Fame quarterback Peyton Manning. Clark hauled in most of his 776 career receptions from Manning when both played for the Colts.

Many of the tight ends sprinted and cut through an eight-camera setup from BreakAway Data, a Los Angeles-based firm that quantifies the minutiae of player movement. BreakAway’s slogan, “Big-time players obsess over small details,” seemed to mesh well with Tight End U’s detail-oriented nature.

This was, after all, a laboratory for elite talent at one of football’s most distinctive positions. NFL tight ends essentially hybridize the pass-catching duties of receivers with the blocking responsibilities of offensive linemen. And the appeal of their versatility is growing as offenses, such as the 49ers’ attack under coach Kyle Shanahan, assign positional duties that are increasingly amorphous.

“To play tight end, you have to have a couple screws loose,” Clark said shortly before measuring his own quickness on BreakAway’s cameras. “You’ve got to be able to do the dirty work. You’ve got to be able to be flashy. You’ve just got to have a little buffet of everything. That’s what makes the position so unique.”

Since his retirement nearly 10 years ago, Clark has shifted to training for the ironman triathlon, a hyper-endurance event that also highlights adaptability. It consists of a 2.4-mile swim, a 112-mile bike ride and a full 26-mile marathon run. Clark finished a half-ironman in Oceanside, Calif., in April and is gearing up to take on the full gantlet at October’s Ironman World Championship on Kona, Hawaii.

So consider this week’s quick deviation back to the gridiron at Tight End U as cross-training for Clark.

“This quick-twitch stuff is not the recipe for the ironman,” he said. “But it’s fun to kick the tires. The hip flexors are feeling it a little bit. And there’s nothing better than this grass. You just feel fast.”

Clark did his speed-testing work alongside Kelce, who quickly pivoted focus to Thursday’s later festivities. Tight End U has housed participants at Nashville’s trendy Thompson Hotel and organized a night out on the city’s famed Broadway strip.

It was a celebration that befitted a position group highlighted by Kittle and Kelce, two players who have developed rock-star personalities that have managed to successfully complement the tight end position’s traditionally blue-collar ethos.

“That’s half the fun,” Kelce said. “Nashville, it’s awesome. We always pick the perfect time, when it’s 100 degrees. Go out, get hammered, run around, have some fun. It’s so unique. … To get all these guys from different cities, from different teams, to hear their stories. There’s nothing going like it in the NFL, really sports, to get a collective group like this all together in one weekend and just bounce ideas off of each other. I love it, man. I’ll be here every year.

“We’re a whole bunch of selfless guys. I don’t know if you could do this in other rooms. I don’t think they’re a collective group. Not in the wide receiver room, not in the running back room. You might have that on the team, but as an overall, tight ends support tight ends no matter what. That’s how it’s always been. It’s just not like that at any other position. That’s just the mentality we have. We’re selfless in terms of how we play and then we’re selfless in terms of wanting to spread the love.”

It truly is a distinctive unity, and it has created a new type of offseason event that’s productive for both a rapidly growing group of players and for the community — with a fine dash of the position’s signature quirkiness thrown in. That’s Tight End U.

“Tight ends are all very similar people,” Kittle said. “We have the same mindsets. We love everybody. We do everything on the football field and we all deal with the same problems as a tight end, whether you’re blocking a guy that’s 300 pounds or you’re running routes against a guy that’s way faster than you. We all have like-minded mindsets. When you put all those guys in the same room, where guys want to get better and guys want to help each other, everyone who comes here is gonna learn something. Whether you learn something on a release, on a block, on tape, you pick something up to add to your game.

“Everyone here is hungry and everyone here wants to be an NFL tight end, so when you put all that hunger together, it’s a big ol’ nasty beast — and that’s what a tight end is.”

(Top photo of George Kittle and Darren Waller: David Lombardi / The Athletic)