The 2012 U.S. Marathon Olympic Trials in Houston on Saturday feature two ridiculously fast races. In the men's race, Meb Keflezighi ran a personal best -- his second in 69 days -- to win in 2:09:08, beating Ryan Hall, Abdi Abdirahman and fourth-place Dathan Ritzenhein. All four went under 2:10, which was completely improbable coming in.

In the women's race, the top four finishers beat the previous Olympic Trials record. Shalane Flanagan edged Desi Davila for the victory in 2:25:37. Kara Goucher finished third and Amy Hastings held on for fourth.

Here are the full U.S. teams for the Olympic marathon.

Men's:
Meb Keflezighi
Ryan Hall
Abdi Abdirahman
Alternate: Dathan Ritzenhein

Women's:
Shalane Flangan
Desi Davila
Kara Goucher
Alternate: Amy Hastings

The women's marathon in London will be held on August 5. The men's race will be on August 12.

NBC will be broadcasting the Trials beginning at 3 p.m. ET on Saturday on a condensed tape delay.