Kansas City Chiefs tight end Travis Kelce just doesn't slow down. Even after four straight seasons of posting more than 1,000 yards receiving and celebrating his 31st birthday in October, Kelce turned in his best campaign ever. In 15 games last year, he caught 105 passes for 1,416 yards and 11 touchdowns. All three figures set career highs. 

Kelce even took his game to another level in the postseason, as he caught 31 passes for 360 yards and three touchdowns in three games. He set the record for most receptions in a conference championship game with 13, and passed Rob Gronkowski for the most receiving yards by a tight end in a single-season in NFL history including playoffs. Kelce simply doesn't slow down, although his passions look a little different in the offseason.

Usually in the summer, Kelce ditches his pads and helmet for his clubs and hits the links. Golf is his game in the offseason, but he maintains the same competitive fire. 

"Up until about two or three years ago I was just out maybe a handful of times, but for the past two or three years I've really been picking it up and playing once or twice a week in the offseason," Kelce told CBS Sports. "Obviously when the season starts up it's hard to get out there, but it's just a fun sport, I'm so competitive even with myself to try to beat my own record or own score. It's something I can do without anybody else being around." 

The difficulty of the sport is something that's also attractive to Kelce, as winning takes mental toughness, which will always dominate physical prowess -- no matter the age. A perfect example of this was on full display this past weekend, as 50-year-old Phil Mickelson became the oldest major championship winner in golf history after shooting a 6-under 282 to claim the 2021 PGA Championship. 

"It was extremely cool," Kelce said of Mickelson's victory. "I remember going to a Firestone tournament in Akron, Ohio, back in the day and seeing Phil Mickelson and Tiger Woods and all the pros go at it -- even at the Masters this year when I went, it's so surreal seeing those guys up close and certainly Phil because he's been doing it ever since I was a kid. And to see how the fans reacted for him this past weekend and to see how dialed in he was -- every shot -- I was locked in on every single shot."

Kelce also explores the fun side of golf in his spare time, and recently teamed up with World Long Drive Champion Kyle Berkshire, LPGA player Cheyenne Woods and golf YouTube star Garrett Clark to take over a DICK's Sporting Goods location for a night and compete in an in-store course challenge. 

"I'll tell you what, I had never hit anything other than a golf ball with a golf club," said Kelce. "That is all I have ever hit, and they had me trying to hit footballs off of tees, basketballs, anything that was in the store that we could try to get in a hoop or in a hole. It was fun. It was an absolute blast. I realized what it was to really go up against the pros in the golf forum, that was my first experience doing that. I was taking notes more than I was dishing out."

Tight End U

While Kelce has been playing plenty of golf this offseason, he also has had a hand in a potentially revolutionary project. Along with several other players, Kelce is assisting in establishing "tight end university," which will be an offseason summit held in Nashville, Tennessee, where tight ends from around the league get together to bond, run routes and help each other improve their games. 

"It recently started when me, Greg (Olsen) and George (Kittle) got on a text and said, 'Yo, let's do this.' Those guys have definitely been the pioneers and the guys really putting it all together and I love the aspect of it. I think it's absolutely needed here in the NFL, I don't think the tight end position gets enough love and gets enough credit for everything we do out on the field, and that's league-wide. I think the more that we bounce ideas off of each other, the more understanding that we get throughout each other's offenses and we can just, you know, learn from each other. Speak about it, talk about it, and then go out on the field and really go through some routes or go through some drills. I think it's definitely going to be something that benefits everybody.

"The tight end room, everybody loves each other. Everybody watches each other's film and I think it's going to be cool to get everybody in the same building to truly try and make this position a staple in every single offense."

Dozens of tight ends such as Darren Waller, Zach Ertz and Mark Andrews have already reserved their spots for "TE U," and Kelce says that they can't get invites out fast enough. At the same time, this is a new project, so they don't want to host more than they can handle. Eventually, however, Kelce says he wants this to be a huge event. 

There is one player who is awaiting the transfer of his transcripts to "Tight End U," and that's Tim Tebow of the Jacksonville Jaguars. He appears to have been invited via Twitter, but nothing is official just yet. Kelce says that he's excited to have Tebow back in the league, and thinks the former quarterback can find success at tight end. 

"Tim Tebow is a household name, man," said Kelce. "Everybody loved the way he played at Florida, loved his passion and how he always left it out there on the field. Who doesn't want that in their facility? I'm excited to see what he does in the tight end room. I know he's not afraid to be physical, so I think in the run game he's actually gonna transition pretty well. In the pass game, I'm just excited to see the opportunities the Jaguars have drawn up for him."

Newfound motivation entering 2021

Golf and "TE U" are fun offseason activities, but Kelce's mind never strays too far from his Chiefs and their preparation for the 2021 season. Kansas City won Super Bowl LIV to cap the 2019 season, and then lost just one meaningful regular-season game in 2020. They made it back to the big game, but were defeated by Tom Brady and the Tampa Bay Buccaneers, 31-9.  

"Just didn't capitalize on opportunities that we needed to capitalize on," Kelce said when asked what went wrong in Super Bowl LV. "It is what it is, I had a few drops, I had a few run assignments that I missed. That's all you can do, is just watch the film and evaluate yourself and then come into work ready to fix it with the guys next to you. I think we got great leaders in this building, I think we got great coaches, great players and this really matters to them. We're going to put in the work, we just have to go out there and fix the things that need to be fixed and be ourselves."

Kelce says he's more motivated than ever to get back to the big game, and he's not taking anything for granted. He wants his second Super Bowl more than he wanted the first. 

"Man, I'll tell you, it definitely turned it up for me. I want this next one more than I wanted the first one," said Kelce. "And just to prove to myself and to prove to our team that we are who we believe we are. I don't think that game really showed our best. I don't think we went out there and played our best and that leaves a sour taste in your mouth that you did that on the biggest stage possible. So it puts some fire in your heart for the passion that you have for this game and it just builds, man. Hopefully we get another opportunity to go get another one."