"His body is starting to show a lot of let-down," Norman said. "He's hit a lot of golf balls.
"He has a lot of power and flexibility and when you have power and flexibility, something has to give - your little joints, you've got Achilles problems, back problems."
But Norman says Woods' physical condition is not his greatest concern.
The Australian, who is also known for his mental breakdowns on the golf course, believes Woods has lost his confidence, particularly with his short game.
"Quite honestly, mentally he's a little unravelled," Norman said. "Imagine, with what we've seen since December last year with his short game chipping.
"Imagine standing over the back of the 12th green at Augusta National and you've hit it over the back and you have to chip it down there, Rae's Creek right in front of you, or the back of the 15th of Augusta National.
"All of those gremlins are going to be sitting in his head."
- AAP