Kelce noted "it was a fun off-season" but said he was now excited to return to training and American football.

Kelce, who turns 37 in October, has won three Super Bowl championships with the Chiefs.

The team did not make the NFL playoffs last year for the first time in 10 seasons. Many believe the upcoming season, which begins next month, could be his last. But the tight end hasn't said whether retirement could be next.

"I have still got a lot of love for this game," he said. "I want to go out there and prove to myself that I can play at a better level than I did last year."

"This is always going to be my sanctuary," he said of being back on the field. "You need to have this time of grinding with the guys, being around them all day, starting to create that chemistry and standard for how we are going to do things. This year it's ramped up even more."

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