Usain Bolt streaked to 100 meters Olympic gold at the Beijing Olympics on Saturday thanks to yam power, his father said.
Wellesley Bolt said his son was partial to the vegetable grown in the north-western area of Jamaica where the sprinter was born.
"It is definitely the Trelawny yam," Bolt senior told Reuters seconds after his son smashed the world record on the way to landing the biggest gold medal in sport.
The yam grown in the parish Trelawny is one of the staples that has made the area famous. It is sold in huge volumes here and much of it is exported. Citizens of the area believe that it has medicinal properties.
"I was very nervous before the race, my heart was pumping. I spoke to him about two days ago and told him that I was getting nervous and he said 'don't worry Dad, I am going to win this one for you'," Wellesley told Reuters from his home, less than 30 minutes drive from the western tourist city of Montego Bay.
"My house has been taken over by more than 100 people from inside and outside the community.
"They are waving flags, beating drums and just making a lot of noise. But this is a special moment and to know that a Jamaican has done this and I am the father of that Jamaican makes me feel special.
"I never expected him to break the world record, but I am proud of my son."
Bolt senior said he sympathized with compatriot Asafa Powell, who finished a disappointing fifth.
"That was surprising to me. I really feel it for Asafa because I felt that he should have performed better," he said.
Bolt's sister Sherine said she knew he would break the world record.
"I expected my brother to win the race and I told my daddy last night that he would do 9.68 seconds. He didn't quite do that, but I am happy still," Sherine said.