Treasure Island viewed from above.
About 50 reality TV contestants are among hundreds of people competing in a series of triathlons and races at San Francisco's Treasure Island this weekend.
Contestants from all nine seasons of NBC's "The Biggest Loser" will be swimming, biking and running in various races scheduled for Saturday and Sunday at the San Francisco Triathlon at Treasure Island.
In the show, overweight contestants attempted to lose weight with the hope of winning a cash prize, but this weekend they will compete in either a triathlon, or a 5-kilometer or 10-kilometer race.
An Olympic distance triathlon, the premier race of the weekend, includes a 1.5-kilometer swim in the harbor area near Treasure Island, a 40-kilometer bike ride on a technical course on the streets of the island, and a 10-kilometer run along the banks of the island.
The Olympic distance race for amateurs starts at 7:30 a.m. Saturday, while the elite race starts at 1 p.m.
The 5k and 10k races are also scheduled for Saturday, while a sprint distance triathlon, which features shorter swim, biking and running courses, is scheduled for Sunday.
A two-day sports and fitness expo is also planned on the island on Saturday and Sunday.
Traffic is expected to be impacted on Treasure Island during the races.
For more information on the weekend's events, as well as a full schedule of races, visit www.tricalifornia.com.