Kristin Armstrong knew she was the favorite to win time trial gold in cycling at the Beijing Olympics. But when she looked at the start list in London, she counted nine riders with a shot.

In the end, there was only one.

The defending champion blistered an 18-mile course starting and ending at Hampton Court Palace south of London earlier this afternoon to win her second straight Olympic gold medal. Her time of 37 minutes, 34.82 seconds was more than 15 seconds better than time trial world champion Judith Arndt of Germany, who took silver.

Olga Zabelinskaya of Russia won the bronze medal.

"My mantra was, You have to live with this ride," Armstrong commented after being celebrated on the Olympic podium "You're only as good as your last result."

It couldn't have been any better.

The former two-time world champion had already gained a second on the field by the first time check, and the advantage had swelled to five by the time she reached the 12½-mile mark.

Armstrong knew she was headed for another gold when she started to pick off riders in the run-up to the finish, including Dutch champion Marianne Vos, who won gold in the road race.

The famously stoic Armstrong let a smile slip as she crossed the finish line, slowing to a stop and then slumping over her bike. She rested just enough to catch her breath before heading to the victory stand and her second consecutive Olympic gold.

Armstrong briefly retired after the 2008 Beijing Olympics to start a family.

"When she stopped, she was on top. You don't lose what you've got," said Armstrong's teammate Amber Neben, who finished seventh. "You don't lose the fact that you're a great bike racer."

It was all gold for Armstrong, even if the path from the Beijing Olympic Games wasn't entirely smooth.

Armstrong thought she was finished after winning the world championship in 2009, but got the itch to ride again after delivering a son, Lucas, in 2010. She got back on the bike and started to win races, only to break her collarbone during a crash in May.

Armstrong admits that she rushed her recovery, getting back on the bike only a couple weeks later. But she also thinks the time off allowed her to refocus on the 2012 London Olympics.

"This is an amazing moment," she said. "A lot of people ask me what the differences were between this and Beijing. I would say this was a much more difficult journey."

"Most of the time, I'm out on the time trial trying to focus, trying to struggle, trying to keep my power up. Today, there are very few moments on the course I remember. All of a sudden I'm like, 'Wow, I'm through the climbs. Wow, I'm here already. Wow, I have to drive it.' I knew if I let off my power one time, the finish goes from first to fourth in an instant," Armstrong told Roadcycling.com.

The mostly flat course that Armstrong turned into her personal playground began at the beautiful and stunning Hampton Court Palace, the 16th century court once favored by Henry VIII.

The race meandered through the Surrey countryside, twice crossing the River Thames, before finishing back at the palace. Riders in position to medal were ushered onto so-called hot seats -- three Royal-style gilded thrones -- to wait out the rest of the riders.

That's where Zabelinskaya spent much of the afternoon.

The bronze medalist in the road race, she was the 10th of a total of 24 riders to leave the start tent, and posted a time more than two minutes better than the next-fastest had crossed the line.

She looked proud, shy and honored sitting on her throne as riders finished.

"I'm really happy to win this medal in such company," she said later, "but I'm also a bit disappointed, because I know I could have gone a bit faster at the beginning."

Linda Villumsen of New Zealand (formerly Denmark) turned heads when she crossed the first checkpoint only a second slower than Armstrong, and the world silver medalist was still second-fastest at the second check.

She struggled over the final leg and finished fourth, less than two seconds off the podium.

Canadian rider Clara Hughes, a former Olympic speedskater, was third at the opening time check before fading to fifth.

"Everybody there wanted me to win. That's what's exciting," said Pooley, who won silver in Beijing. "The number of medals that are on the table, I really don't give monkeys about. We gave our best. I would not be there if I didn't want to try and win."

Arndt was considered the biggest challenge to Armstrong after her time trial victory at the world championships. The silver medalist at the 2004 Athens Games, she was fifth at the first time check but managed to pick up her pace over the final 12 miles to earn another silver.

"You have to have a good day, and I had a good," Arndt said. "I think I had a good race."

Just not as good as Armstrong.

"I'm really happy about this silver medal," Arndt said, before dropping her voice to almost a whisper. "Of course, my goal was to win gold, but if you asked me yesterday, I would have named Kristin the favorite to win."

Former time trial world champion Emma Pooley of Great Britain, who was one of the pre-race favorites, was disappointed with her finishing 6th in today's time trial, but finished the time trial to cheers from a huge home crowd.

"You always have to push your hardest and I did. I don't think I could have gone any faster. In time trial you can't affect anyone else. I'm really disappointed but if someone else is faster than you, you can't do anything," Pooley told Roadcycling.com.

"I was really pleased to help Lizzie (Armitstead) in the road race. I just wish we could have gone up Box Hill in the time trial," the 29-year-old added referring to the lack of climbing meters on today's route in her home country.

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