NEW YORK (WABC) -- 5,000 athletes worked to beat the extreme heat as they swam, bicycled and ran through New York City.
The 18th annual 2XU New York City Triathlon kicked off Sunday morning.
The first group of athletes jumped into the Hudson River at about 5:50 a.m. for the swim portion.
Athletes then entered the water every 20 seconds until 7.
Participants swam nearly a mile in the Hudson River, then biked nearly 25 miles on the Henry Hudson Parkway, ending with a 6.2 mile run in Central Park.
The 2XU New York City Triathlon, the only international distance triathlon in New York City, includes pros, paratriathletes (physically challenged) and age group athletes.
Beyond six fully-stocked fluid stations, organizers say they increased the amount of misting stations and medical support throughout the event due to the heat.