BARCELONA, Spain -- The most stressful part of Emilie Heymans' gold-medal performance came after she took her final dive.

The Canadian won the 10-meter platform Wednesday in the World Swimming Championships after two favored Chinese competitors came up short in their final efforts.

Heymans, who won silver in the 10-meter platform synchronized in the 2000 Olympics and gold in the 1999 Pan Am Games, edged Lao Lishi and Li Na because of a final dive that began with a somersault and ended with a twist.

Heymans went into the final in fifth place. Li and Lao were leading the competition.

"I didn't know the situation when I came out of the pool," Heymans said. "My coach told me I had a chance of winning.

"I started getting stressed about how the Chinese would dive. I knew I would get a medal but I didn't think I'd get the gold."

Heymans' gold was Canada's first of the championships.

Russia tops the medal table with four golds and seven overall.

Russia's Vladimir Diattchine won the 10-kilometer open-water swim, which came just 18 hours after countryman Alexander Dobroskok took the men's 3-meter springboard title.

Earlier in the week, Dobroskok was the gold medalist in 3-meter synchronized, teaming with Dimitry Sautin. Evgueni Kochkarov claimed gold in the 5-kilometer open swim.

Russia's women's water polo team also is unbeaten. The men, among the favorites in the field, were edged 10-8 by two-time defending champion Spain.

Out in Barcelona's harbor, Diattchine won in 1 hour, 50 minutes, 58.8 seconds. He was 7.7 seconds faster than Christian Hein of Germany.

Italy picked up its second gold medal, with Viola Valli cashing in again. She won the 10-kilometer women's swim in 1:59:49.9, 1.2 seconds faster than Angela Mauer of Germany.

Valli weighs just 114 pounds and stands 5-foot-2.

"My secret is in practice and having the tactics to have a great race," she said. "In long distance you don't necessarily need to have a huge body."

Japan picked up its first gold medal of the championships in the free-combined program in synchronized swimming. The United States and Spain shared the silver medal.