LONDON - It requires a certain fearlessness to race in the elite ranks of BMX. When the metal starting gate drops, eight riders barrel down a hill, navigating banked hairpin turns and big-air jumps in a chaotic blur to the finish line.
The frequent crashes leave hands bloodied and egos bruised. At the Olympics, they also extinguish dreams, as Alise Post discovered Friday. Post, of St. Cloud, shook off one wipeout in the semifinals of the women's race on the BMX track in Olympic Park. The second one knocked her out of the competition, leaving her dazed and saddened as she ended the London Games without reaching the eight-rider final.
The rashes of crashes ruined the medal chances of the four U.S. athletes in Friday's semifinals and finals. The best they could manage was Brooke Crain's eighth-place finish in the women's final, and Connor Fields' seventh-place showing in the men's final. Mariana Pajon of Colombia won the women's race, while Maris Strombergs of Latvia won the men's.
Post looked wistful as she watched Pajon receive her Olympic gold medal, only the second ever won by her country. Post's torn sleeves and black-smeared pants told the story of her day, which ended when she was helped off the track, walking over the finish line rather than racing over it.
"I couldn't tell you what happened," said Post, who was not seriously injured when she crashed on the final straightaway. "I was in utter shock with what was going on. I fully expected myself to be on the podium.
"I was telling myself that just being able to make this team after what I've been through the past year, I proved to myself I was better, faster and stronger than the other riders. I felt that way all day. It just didn't go my way."
Post only got back on her bike eight months ago. She blew out her right knee in July 2011 and underwent reconstructive surgery and a long rehabilitation, missing the first part of the qualifying period for the Olympics.
She entered the London Games on the upswing, having made the finals of every supercross World Cup this season. One of the top athletes in this sport of survival, Post threw herself right back into the high-energy fray. With everything from reggae to punk to Bon Jovi providing the bass-heavy soundtrack, 16 women and 16 men raced on an unusually bright day in Britain, under a sun so intense that spectators used their omnipresent umbrellas for shade.
The semifinals consisted of three runs. To advance to the final, Post needed a total score that ranked among the top four in her heat of eight riders. She finished third in the opening run, when one rider -- Brazil's Squel Stein -- was carried off on a stretcher after a nasty crash.
In the second, Post stormed out of the tunnel in the middle of the course, riding aggressively to try to move up. Venezuela's Stefany Hernandez squeezed in on her, causing Post to slide sideways and fall. Still, she remained in contention to make the final if she could record a solid finish in the last race of the semifinals.
Post drew the outside lane for the third run, a poor position on a track that favored riders on the inside. "With the Olympic hype, everyone was trying to ride above their heads a little bit," she said. "I tried to keep calm out there and felt I was in a pretty good mental state. But I knew I had to be in the top three or four to get in [the finals], so I was charging pretty hard. And unfortunately, that last straight is a control-your-speed kind of straight."
She lost control and went down. Post tried to rise on her own but fell back to her knees and crawled to the side of the course, where two workers helped her get to her feet. They stood on either side of her and helped her walk the final yards to the finish line, where she was greeted with applause.
In 2008, when BMX joined the Olympic program, Post had the speed to make the U.S. team -- but she was only 17 years old, two years under the minimum age requirement. Now 21, she plans to try for a second Olympic berth in the Rio Games of 2016.
"I'm just trying to walk away with my chin up," Post said. "Hopefully, I'll come back and be ready to roll for the next [Olympics], and hopefully get a better result. I have to say, I feel I've let myself down and let everybody else down a bit. I'm a bit disappointed. But being here is a feat in itself."