Jamaican sprinter Usain Bolt leads the way.
The 2:28 debutante is ready to step in and race next Sunday's Olympic Marathon.
The marathon world-record holder has been hampered by a foot injury.
She will still compete in the Games.
Four women will vie for one spot on the Olympic marathon team on Sunday.
He just ran a 60-minute half marathon in Vienna.
Austria's largest marathon takes place on April 15.
The Ethiopian wants to show the world he's not done yet.
Paula Radcliffe is running the Vienna Half in April.
He thought they were at the end of August.