Jennifer Lopez1 of 23
Record-breaking singer, actress and dancer, J.Lo, known for her role in "Selena," and singles like "Jenny from the Block," plus a myriad of other accomplishments, decided to transform into another kind of triple threat as a triathlete. She completed the Nautica Malibu Triathlon in 2008 with a time of 2:23:38.
America Ferrera2 of 23
The "Ugly Betty" and "Superstore" actress adopted the multisport lifestyle in order to gain self-confidence and refocus, racing in the Olympic distance of the Nautica Malibu Triathlon as a part of Team in Training, which helps raise money for the Leukemia and Lymphoma Society. However, Ferrera not only uses triathlon as a method of developing her own inner-strength, she uses it to help inspire other women and girls to push their boundaries as well.
Gordon Ramsay3 of 23
Ramsay isn't just the foul-mouthed star of "MasterChef" and "Hell's Kitchen." He's also pretty accomplished at the swim-bike-run, too, even competing at the 2013 IRONMAN World Championship with a time of 14:04:48.
Melanie Chisholm4 of 23
Better known as Sporty Spice, Chisholm is definitely living up to her nickname, taking on triathlon after overcoming clinical depression and an eating disorder. Since crossing her first multisport finish line in 2011, the singer has completed a plethora of races, including the London Triathlon and the 2016 Blenheim Palace Triathlon.
Jimmie Johnson5 of 23
Johnson, a racecar driver and winner of seven NASCAR Cup Series, is perhaps the most dedicated triathlete-celebrity on this list, having not only raced in multisport events but also started his own race. He's also an advocate for USA Triathlon's Check Yourself share the road initiative. With a 70.3-distance race already under his belt, as well as over 10 other shorter triathlons and a 100-plus mile bike climb up Mt. Mitchell, his ultimate goal in the sport is to hear his name called as he crosses the finish line in Kailua-Kona, Hawaii, at the IRONMAN World Championship. But only after he finally retires from the racetrack.
Matthew McConaughey6 of 23
A-lister McConaughey, who starred in "Dallas Buyers Club" and "Magic Mike," also starred in his first triathlon back in 2008 when he swam, biked and ran his way to a 1:43:48 time at the Nautica Malibu Triathlon.
Max Greenfield7 of 23
It's well-known that Greenfield of "New Girl" and "Veronica Mars" fame is really into CrossFit. But what fans of his often-pretentious character Schmidt don't know is that he's also a triathlete, finishing the 2012 Nautica Malibu Triathlon in 1:48:09, annihilating the four-mile run in just 29 minutes to take fourth in the celebrity male division.
Ellie Kemper8 of 23
Fans of "The Office" are sure to remember Michael Scott's Dunder Mifflin Scranton Meredith Palmer Memorial Celebrity Rabies Awareness Pro-Am Fun Run Race for the Cure. But did you know Kemper (Erin), alongside Ed Helmes (Andy), Oscar Nunez (Oscar) and Paul Lieberstein (Toby) raced in the 2011 Nautica Malibu Triathlon?
Natalie Morales9 of 23
Morales, a journalist working for NBC News, is best known as the west coast anchor of "The Today Show." However, she moonlights as an endurance athlete, and has completed various triathlons, including the Malibu Triathlon, War at the Shore Triathlon and South Beach Triathlon. She's also an avid runner and New York Marathon finisher.
Sanjay Gupta10 of 23
Neurosurgeon, CNN medical expert and triathlete—is there anything Gupta can't do? The Atlanta resident is a long-time multisport athlete, racing in the Nautica Malibu and Lake Lanier triathlons, but he doesn't just compete for his own health. Gupta uses his platform and knowledge to get others into the sport as well, leading a group of amateurs as part of the CNN Fit Nation Team.
Jennie Finch11 of 23
An Olympic champion softball player, Finch had no intention of giving up her active ways after hanging up her gloves in 2011. She turned to the swim-bike-run and completed her first triathlon in 2013 at the New York City race. She finished with a respectable time of 2:51:15.
David Denman12 of 23
You might know him as Roy from "The Office," but did you know this actor also spends his time on the swim-bike-run as well? Denman raced in the 2011 edition of the Nautica Malibu Triathlon, finishing with a respectable time of 2:30:11.
Rainn Wilson13 of 23
"The Office" co-stars really love the triathlon it seems. Add another to the list from the hit NBC series, as Wilson, who played everyone's favorite beet famer, Dwight, raced in the 2012 edition of the Nautica Malibu Triathlon, finishing with a time of 2:08:28.
Ryan Sutter14 of 23
The first winner of "The Bachelorette," Sutter found love in more than one place, picking up triathlon a year later and racing in the prestigious IRONMAN World Championship in Kona-Kailua, Hawaii, in 2004, finishing with a time of 11:38:28. Years later he took on another 140.6—this time in Lake Placid, New York—finishing in 11:06:37.
Sean Astin15 of 23
Known for starring in "Rudy," "The Goonies" and "The Lord of the Rings" trilogy, Astin is also a triathlete, tackling IRONMAN 70.3 Vineman, as well as the IRONMAN World Championship, in 2015.
Apolo Ohno16 of 23
The American speed skating star of the 2002, 2006 and 2010 Olympics, Ohno is an eight-time Games medalist and two-time champion. And after accomplishing everything he could on the short track, Ohno turned to a different sport, completing his first full IRONMAN in Kona with an impressive time of 9:52:27.
Hines Ward17 of 23
After completing his successful NFL career with the Pittsburgh Steelers, Ward turned to triathlon in 2011, working his way up the multisport ladder all the way to the IRONMAN World Championship in 2013 where he finished in 13:08:15.
Mario Lopez18 of 23
Host of "Extra," Lopez is better known as the jock A.C. Slater from "Saved by the Bell." The athlete mentality never left him as Lopez took on his first swim-bike-run in 2009 when he raced in the Nautica Malibu Triathlon, posting a time of 2:03:17.
Tony Kanaan19 of 23
Not just an Indianapolis 500 winner, Kanaan also swam, biked and ran his way to a finish at the IRONMAN World Championship in 2011 with a time of 12:52:40. But he didn't stop there. The racecar driver uses his platform to advocate for cycling and a more active lifestyle, spending time on local community group rides when not at the racetrack.
Claire Holt20 of 23
Holt, who played Rebekah Mikaelson in The Vampire Diaries," as well as its spin-off show "The Originals," had her first taste of triathlon in 2012 when she finished first in the female celebrity division of the Nautica Malibu Triathlon, posting an impressive time of 1:44:31.
Nick Lachey and Vanessa Minnillo21 of 23
A little competition never hurt anybody. Lachey, a musician, and Minnillo, a TV personality, put their relationship to the test, racing in Roselyn Sanchez's ("Devious Maids," "Without a Trace") Triathlon for Life to benefit the San Jorge Children's Foundation in San Juan, Puerto Rico.
Felicity Huffman22 of 23
Starring on the famed TV show "Desperate Housewives," as well as "American Crime" and "Frasier," Huffman is also an accomplished triathlete, completing more than 10 races, finishing under 1:47:00 each time out.