The Americans bring a strong field to this year's race in the heart of Manhattan.
The repeat gold medalist is adamant that he's clean.
The Los Angeles musician completed her first 100-mile race in 2010.
She won gold for Team USA at the Mountain Running Championships on Sept. 7.
Five meet records and 11 world-leading performances were the reason.
The 27-year-old Kenyan will be looking for a fast time on Sunday.
A retiree clocked 5:16 miles for 6.2 miles.
He wore a shirt that said "Victory" during his run.
The legendary American runner would love to own a two-seater Mercedes, but drives a Honda Civic.
18,000 time-qualifier slots remain, and the process continues on Wednesday.