Topeka ? Of all things, the triathlon is what the Barnoskie family has in common.

It’s unique, and it’s a testament to the remarkable athletic genes being passed around the family tree. The spotlight now is on Katie and Marcus Barnoskie, a teen sibling duo making waves (and tracks) in the triathlon, one of sport’s most grueling challenges.

The two, with their trademark Oakley sunglasses wrapped around their eyes, competed in the short-course race of the Topeka Tinman Triathlon on Saturday morning at Lake Shawnee — not that it’s exactly short by most people’s standards. It started with a 300-yard swim in chilly Lake Shawnee, then to the bikes, where a nine-mile trek awaited before ditching the ride and running the final three miles of the race on wobbly, tired legs.

Sounds painful, but the Barnoskies love it.

“I love swimming and biking, and I love doing cross country,” said Katie, who runs cross country and swims for Lawrence High. “This brings them all together.”

The two had a remarkable day Saturday. Marcus, 15, won the family battle with a short-course time of 52:03. His race placed him eighth overall in the men’s short-course division, with seven men over the age of 18 ahead of him.

Not to be outdone, Katie achieved a year-long goal by being the overall champion of the women’s short-course race, finishing in a time of 53:00. She placed fourth overall last year and had been hungry to impress so close to home ever since.

Both siblings have been ranked nationally in their age groups by USA Triathlon. Marcus will be a sophomore at LHS this fall. Katie, 17, will be a senior. With the age and gender differences, the two are putting up comparable times these days, and it’s quite beneficial — and motivating — that way.

“You just keep thinking that you want to beat her,” Marcus said with a laugh, “and rub it in her face.”

Lawrence High students Katie Barnoskie, left, and her brother, Marcus, wade in Lake Shawnee before the start of the Topeka Tinman Triathlon. Katie Barnoskie won the women's short-course race, and Marcus was eighth in the men's short-course race Saturday in Topeka.

Really, it’s less vicious than that. Katie and Marcus often train together several times a week and get priceless help from their parents — father Randy, a former triathlete, and mother Angela.

Come race day, though, the siblings usually are on their own. As was the case Saturday, Marcus and Katie often don’t see each other once the races get under way. Marcus’ heat started 10 minutes before Katie’s, which naturally made it tough for the parents, who constantly were running around to different stations trying to cheer the two on.

It’s nothing Randy and Angela aren’t used to, though. The siblings compete in triathlons every weekend during the summer, including an Olympic-length triathlon last weekend in Tulsa, Okla., and the Flint Hills Triathlon the weekend before that in Manhattan.

6Sports video: Barnoskies take on triathlon

Yes, race day is a family affair in the Barnoskie household. That’s probably why Katie and Marcus are so good at such a young age.

“It’s a really fun sport,” Katie said, “especially when I have my family competing and training with me.”