"In all honesty, it's a huge challenge," the seven-time Tour de France champ, 36, told local station WNBC at the starting point of the race, near the Verrazano-Narrows Bridge on Staten Island.
Armstrong, who said he trained more this year than he did in 2006 (his first time in the NYC challenge), also exhibited some, uh, interesting pre-marathon behavior over the past week – nuzzling with Ashley Olsen, and hitting a series of fashionable watering and dining spots around town.
Joining the approximately 39,000 other runners on Sunday, Armstrong said he was "pain free" this year. "It was so hard last year," he said. "I had no idea what I was doing."
Still, last November he finished in just under three hours, and this year he said his aim was to come in at 2:50.
As it turned out on Sunday, he came in at 2:46:42. As Armstrong in his yellow shirt, dark shorts and sunglasses approached the finish line, his image was broadcast on an enormous TV monitor that was perched overhead – which got the crowd cheering, as the musical theme to Entourage was played.
(Top male runner on Sunday, with a time of 2:09:04, was Martin Lel of Kenya, who'd previously won the NYC Marathon in 2003.)
'A Lot Better Than Last Year'"It's a lot better than last year. I'm happy about that," Armstrong said afterwards, citing "great weather [and] great people."
Asked if he'd return to pro sports, Armstrong said of the race he'd just finished, "I do this stuff for fun. ... I'm a dad. I'm a cancer advocate ... but pro sports are done for me."
When Sunday's race was barely an hour old, a TV reporter sidled up to Armstrong and asked if he'd brought along an entourage.
Not breaking his step, the retired cyclist acknowledged those keeping pace with him on the street and pointed out "a dude with green hair. I got like 20 languages around me ... the great people of New York."
But by the time Armstrong hit the Bronx, the dude with green hair was no longer near.