(Image source from: Ironman Arizona)

Fans, family and friends queued up along the Tempe Town Lake on Sunday morning to support their favorite athletes, as nearly 3,000 athletes from 39 countries took to the lake to kick off the first leg of this year's grueling triathlon - Ironman Arizona.

The event kicked off with a 2.4-mile long swim in 60-plus-degree waters followed by a 112-mile bike ride.

"If you think about it, our athletes have a full-time job, they have family obligations and kids to take care of, in addition to that they're training on average 10 to 20 hours per week and finally culminating in about a 20-hour training week at the end of their training season," said Dave Deschenes with the Ironman Foundation.

Many of the athletes, aged between 18 to 80 years old, finished their 17-hour long swim and rushed to the bike before running a full 26 miles marathon.

The top 50 will contest in the Ironman World Championship in Hawaii.

AW: Suchorita Dutta Choudhury