Well, two-time Masters Champion Bubba Watson says it's his age.
"Just because I'm getting older, and [the] inflammation in my body, Waking up with better sleep," he said. "That was the two things that I was focused on with a seven-year-old and a four-year-old at the house and playing golf all day."
"I needed some energy fast, and so for me, it's all about sleep and I'm trying to get the body right," he added.
Watson also talked about what's next for him.
"We've got the PGA championship. Obviously, we know the story of Tiger Woods winning the Masters, and so it's going to be, I would say controlled chaos up here with the fans pulling for Tiger and being a part of that and fill in the atmosphere's going to be amazing up here in New York at Bethpage," said Watson.