NEW YORK (AP) _ Parkinson's disease has diminished his voice and slowed his body, but Muhammad Ali still exercises regularly in a gym at his home, punching a heavy bag and sometimes sparring playfully in a boxing ring, his wife says.

He hasn't driven a car in 15 years and ``he's no longer the type to pick up the phone and call friends the way he used to, but we converse,'' his wife, Lonnie, said in an interview in the March-April issue of Neurology Now, an American Academy of Neurology magazine for patients, their families and caregivers.

``Don't get me wrong, it's not like he's sitting there espousing rhetoric, but his words still carry impact, they're still very important,'' she told the magazine. ``You absolutely can understand what he wants, what he says, what he's thinking.''

Ali, 64, has been in the public eye in recent months. He was unable to walk unassisted but still spirited in November when he was awarded the Medal of Freedom by President Bush, and playful again a few days later at the dedication of a centre named for him in Louisville, Ky.

The magazine piece offers a rare glimpse of his home life in Berrien Springs, Mich.

``Muhammad is getting older,'' Lonnie Ali said. ``And we're tired of being on the road all the time. We have a 14-year-old at home and he's in school, so we don't like to leave him behind so much.''

Asked whether his busy travel schedule is too much to handle, the boxing great gave the magazine a single hoarse word: ``No.''

His daughter Rasheda said that he loves magic tricks and that he amuses his grandchildren by drawing pictures for them.

Because his disease has interfered with his balance and posture, she told the magazine, ``when I'm with him, I just hold his hand while we walk.''

She took him to the new version of the movie King Kong, she said, and he ``just loved it. ... He ate all my popcorn and we just had a wonderful time.''

Asked what he would tell his fellow Parkinson's patients if he regained his voice, she said, ``He would tell them what he tells me when we're alone and we're talking. He'd say, `Don't give up. Believe in yourself.'''