In a celebratory Instagram post, Ruah shared a Reel of her journey to completing the iconic event alongside her former NCIS cast members Caleb Castille, Duncan Campbell and David Olsen.
"Sunday was amazing! Not only did I achieve a huge goal (look mom I did it!) but I did it alongside wonderful friends AND the @malibutri raised over $1.2 MILLION dollars for @childrensla," she captioned the post.
"Congrats to everyone who participated! & Thank you so very very much to all who donated! The whole journey has been unforgettable. Shall we do it again next year?"
The actress, who is best known for her role as Kensi Blye in the iconic police drama, completed the triathlon in support of Children's Hospital Los Angeles.
Ruah took to Instagram last month to announce that she would be taking part in the event with her former co-stars, in an attempt to raise $10,000 for the worthy cause.
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"Alright, for the last few years I have taken part in the Malibu triathlon to raise funds for the children's hospital in Los Angeles. But I've always only done the running portion of the race as part of a relay team," she explained.
"This year, however, because I turn the big 4-0 in December, I decided to gift myself an entire race so swimming, biking, and running."
"We've also got a little team of people together to help us raise funds and that is Caleb Castille, Agent Roundtree, Duncan Campbell, Agent Caster, and my very own hubby David Olsen who played Tom Olsen on NCIS LA."
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