CHULA VISTA (CNS) - John Nunn of Chula Vista finished 43rd Saturday in the men's 50-kilometer walk, finishing what he called "the most grueling, physical race that there is in the Olympics," in a personal best time of four hours, three minutes, 28 seconds.
The 34-year-old Nunn moved up 14 spots over the final 20 kilometers. He was 57th after 30 kilometers, 54th after 35, 52nd after 40 and 47th after 45.
What began as a field of 63 walkers raced 50 laps on a two-kilometer (1.2-mile) loop course in London which started at The Mall, then headed toward Buckingham Palace, around the Victoria Memorial and up Constitution Hill toward Hyde Park Corner before returning to The Mall to complete the loop.
Sergey Kirdyapkin of Russia won in an Olympic record 3:35:59. Jarred Tallent of Australia was second in 3:36:53 and Tiafeng Si of China third in 3:37:16.
Nunn was the lone American in the race.
Walkers are required to have one foot on the ground at all times. The leading leg must be straight from the moment it is first in contact with the ground. Judges are stationed at points along the course to examine the walkers' technique.
If a judge is unhappy about any aspect, he or she will show a yellow paddle to the walker as a warning. If a walker is clearly not complying, the judge will show a red paddle. If a walker is shown three red paddles by three judges, he is disqualified.
Eight walkers were disqualified and four failed to finish.
"The 50K is a brutal race," Nunn told NBC.
Nunn qualified for his second Olympics by winning the Olympic trials in Santee on Jan. 22. He was 26th in the 20-kilometer walk in the 2004 Games and failed to qualify for the 2008 Games.
"It has been a long road to get back," Nunn said after winning the Olympic trials. "My daughter (Ella) was 6 months old when I went in '04 and I really wanted to give her a chance to come and see it again."