After each biathlon competition in careers that have spanned 15 years, Tracy Barnes and her twin sister Lanny always go on a hike to reflect on everything that has happened.

After the announcement of the U.S. biathlon team last weekend, they went on a hike that neither sister will ever forget. Tracy, 31, said she was declining her spot on the team in Sochi — so that Lanny could take her place.

“It just was one of those moments that I think changed my life forever,’’ Lanny told TODAY Thursday.

“She’s having a great year, and I think when you care enough about someone you’re willing to make that kind of sacrifice,’’ Tracy told TODAY.

Lanny was sick and missed three of the final four qualifying races in Ridnaun, Italy, and appeared to be out of the running for one of the five spots on the team in Sochi before her sister made the decision.

“Usually I always know what Tracy is thinking, and she shocked me,’’ Lanny told Matt Lauer on TODAY Thursday. “I didn’t see this coming, and I was like, ‘Tracy, there’s no way. This is your spot. You earned this.’ She was very adamant about me going and she said, ‘No, I want you to go.’ It was a very emotional moment for both of us.”

“I think right away when I heard she got sick (I made the decision) because I knew that the likelihood of her making the team was pretty slim,’’ Tracy told Lauer. “I’ve trained with her for 15 years right alongside her. I know how hard she works. I know how much she wants it. All of us who are training for something like that, that’s your dream, that’s your goal, that’s what you work towards. I think I felt so strongly about this, and that outweighed any effort that I wanted to do to go to Sochi.”

The twins from Durango, Colo., competed together at the 2006 Olympics in Turin, but only Lanny made the team in 2010 in Vancouver, where she had the highest finish of any U.S. woman in the 15-kilometer event since 1994. Lanny appeared on track to make the team in Sochi before illness hit.

“It was brutal,’’ Lanny said. “It’s hard to explain how you can train so hard for something and luck just wouldn’t have it your way. It was disappointing for sure.”

“I was real disappointed when I heard that she was getting sick,’’ Tracy said. “In this sport, you have to be 100 percent to perform at the level that we need to perform at. I kind of knew that things weren’t going to go well for her. It was completely disappointing.”

Lanny finished one spot behind Tracy in qualifying, so when Tracy declined her place on the team, the competition committee then selected Lanny for her third Olympics.

“When you work as hard as you do to be at that level of an athlete, the Olympics is the pinnacle,’’ NBC biathlon analyst and former U.S. biathlete Chad Salmela told TODAY. “And to give that up is giving up everything.”

By going in place of her sister, Lanny now has the increased pressure to perform at a high level, and that’s just the way she likes it.

“I want to do my best for Tracy, and I always do better under pressure, so I’m definitely going to push as hard as a I can and just fight that much harder for her,’’ Lanny said.

(Copyright (c) 2014 NBC News Channel. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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