PHOENIX (AP) - Muhammad Ali visited a hospital here to lend his weight to the fight against Parkinson's syndrome. The former heavyweight champion, 54, his left hand twitching and his walk slow and plodding, on Tuesday dedicated the Muhammad Ali Parkinson Research Centre at Barrow Neurological Institute. Dozens of elementary school students turned out to catch a glimpse of Ali, shake his hand or get an autograph. "He's a hero," said Chad Rocco, 11, who gave Ali a big hug after handing him a book of inspirational poems and essays from his classmates at Longview Elementary School. "He was a great boxer," Chad said. "But with his disorder, he's a better hero." The centre, which is expanding under its new name, provides services, education and research on Parkinson's syndrome and related disorders. Ali suffers from the neurological disorder, which weakens muscle control in more than one million Americans.