Mr King ran successfully in sports meetings in New Zealand and Australia. He said at one particular event he won three championships - the quarter mile, half mile and mile.
"I liked it because I knew I could win," he said.
Up until a couple of years ago Mr King was still going on long walks and mowing his lawn. While he joked he was "lucky" to live so long he said keeping active probably had something to do with it - he's always loved sports, including rugby.
Mr King was born in 1914, in Manunui in the King Country and was one of 10 children - seven girls and three boys.
He grew up in Mangawhai, in Northland, and followed in his father's footsteps and became a dairy farmer.
Mr King married his wife Alice in 1939. She died about 10 years ago and a picture of her sits on his dresser.
"There she is smiling down on me. She was a very hard worker," he said.
The couple had nine children together - seven boys and two girls. Three of Mr King's children have died but he has plenty of grandchildren and great-grandchildren.
One of his son's, Leon, 69, said although he needed reading glasses, his father could still read the newspaper without glasses.
"He's done very very well," Leon said.
A family celebration was held at Leon's home in Hikurangi on Saturday and a celebration will be held today at the rest home.
Mr King said it was "unbelievable" watching the world change. When asked if his goal was to get to 103 he said: "we'll see".