All-around champions Kohei Uchimura of Japan and Simone Biles of the United States added a gold medal in an individual event Sunday to cap sterling performances at the gymnastic world championships.

Uchimura won the parallel bars to give Japan a fourth gold out of seven men's events.

Biles again showed her power and jumps on the floor to complete the best overall American performance at a worlds. Like Uchimura, she finished with two gold medals and four overall.

The U.S. team ended with 12 medals, exceeding its previous high of nine at the 2005 Melbourne championships. With a dozen medals, the Americans had almost double those of their nearest challenger, Japan.

"We are ready to go for Rio," U.S. women's coach Martha Karolyi said. "It is usually the year after the Olympics can be a little bit hard and rocky, but we were able to find again some of the old generation."

One such gymnast was defending champion McKayla Maroney, who won the vault Saturday. Then there was Biles, who showed maturity beyond her 16 years to win the all-around and back it up Sunday with gold in the floor.

"All the hard work has paid off," said Biles, who finished with four medals overall to anchor the U.S. performance. "It is so exciting to be part of that. I cannot ask for anything more."

The performance of the day came from Olympic high bar champion Epke Zonderland of the Netherlands, who set the Sports Palace alight with a routine full of gravity-defying leaps to win the last event of the championships. He edged Fabian Hambuechen of Germany and making Uchimura settle for bronze.

After winning a record fourth all-around world title early in the week, Uchimura was at his best again in the parallel bars, enough for a shared gold with China's Lin Chaopan.

Already acknowledged as the greatest gymnast ever, Uchimura won his first gold in the parallel bars. Usually serene and withdrawn, Uchimura was pumping his fists and flashing big smiles to the thousands in the stands after John Orozco of the United States took third place.

Aliya Mustafina won Russia's first gold medal of the championships, edging Kyla Ross of the U.S. on the balance beam.

Mustafina, the 2010 all-around champion, was nearly flawless as she twirled, twisted and jumped at will on the narrow beam, and then watched Ross and Biles fall short of surpassing her. It was Ross' third silver of the championships. Biles took the bronze.

In the men's vault, South Korea's Yang Hak-seon dominated again. The defending and Olympic champion brought a difficult new vault to Antwerp and performed it well enough to slip past American rival Steve Legendre. Kristian Thomas of Britain was the bronze medalist.