Transcript for US Olympic ski jumper Sarah Hendrickson on overcoming injury to compete again
numbers. 20,000 jumps at three seconds each. And U.S. Ski jumper Sarah Hendrickson has spent 16 hours of her life in flight. Do you have time to take a breath or are you just holding everything so tight? I'm not sure about breathing or blinking. It's kind of hard to describe, but it's the best feeling in the world. Reporter: At this year's olympic trials Hendrickson didn't just fly into first place -- She knows exactly what she just did. Reporter: -- She arguably soared into sports history. It was amazing. I honestly didn't expect to win. Reporter: Hendrickson is just 23 years old, and four years ago she became the first woman to ski jump at an olympic games ever. I was fortunate enough to have been number one in Sochi. So it was a very historical event. I'm honored to be a part of it. Reporter: For nearly 100 years the sport was almost the emblem of the winter games. A ski jumper soaring down a mountain and another crashing in a windmill of limbs and skis. And the agony of defeat. Reporter: Immortalized by ABC's "Wide world of sports." A good jumper can clear the length of a football field. Traveling at speeds of up to 60 miles an hour. What many don't realize, though, is for 90 years women were kept from competing because officials said they were too frail. For a lack of filter, our uteruses would fall out. We weren't strong enough. It would inhibit our ability to have children. Yeah. Honestly a laughing matter. Of course there are risks. Look at downhill. Look at free skiing. There are risks in that too. So why all of a sudden is it just ski jumping that's having these childbearing issues? Reporter: Women's olympic sports are have typically made slower progress than men's sports. It wasn't until 1996 that soccer opened up to women, when Mia hamm and the U.S. Team finally won gold. Women's boxing wasn't allowed until 2012. In many ways you were the poster child of this sport for women. Yeah. And for me that's been an honor. Yeah, it is definitely pressure. But again, I just love ski jumping. It's what I do. Reporter: Born and raised in park city, Utah, Hendrickson was on skis by the age of 2. Jumping by 7. By 10 she was such a future prospect that she was interviewed by ABC news cameras. I hope to get to the olympics one day if they ever do get in the olympics. You'd compete in the olympics? Yes, absolutely. Girls are exactly like boys because, I mean, they -- we've been jumping for just as long as they have. And that's the way it always should be. Reporter: That was way back in 2006. My brother was in it. So I was sick of waiting for him in the car. It seemed like a perfect fit. And honestly loved it from the start. And I was always fearless as a kid. Reporter: And she was equally fearless as an adult. By 2013 she claimed four world cup wins. Including this one in Oslo. But then a catastrophe. I basically destroyed my right knee, tearing my acl, MC off the bone. 80% of my meniscus was damaged. And yeah, it was pretty brutal. Did you know immediately that this is really bad? I tried to convince myself that I was okay. But yeah, it was pretty much as bad as it can get. Reporter: After intense rehab she made the 2014 U.S. Olympic team but her knee kept her from doing her best. I had a dream of winning gold. But with an injury like that it just kind of wasn't realistic anymore. Really just had to enjoy the games for its experience and for the historical moment for women's ski jumping. Reporter: First to break that barrier she was featured in this Visa commercial. Now women get a chance to fly. Reporter: It wasn't always a sport that offered equality. In fact -- Still doesn't. Reporter: In the olympics the women get a chance to medal in only one ski jumping event. The men compete in three. Hopefully one day we'll be equal. Reporter: Hendrickson reinjured that bad knee in 2015, tearing her acl for a second time. She's now spent years building it back up. I have good days and bad days still. I can't even hardly walk around a city without having pain or walk around the grocery store, that type of thing. And once they bend into a knee five times, it's not Normal again. Reporter: Her training regimen is brutal. From the slopes to the gym to a wind tunnel where Hendrickson works to perfect her air control and body positioning. Before she heads out to south Korea, she gives me a lesson. We do this on a daily basis to practice our technique, right? This is the track. I think the scariest part that people think about ski jumping is once you're going down you can't stop, your skis are stuck in an ice track. So jump before you fall off the ramp. Reporter: She makes it look easy. Lower, lower, lower, lower. Jump! I jumped low and late. No, you were early. Reporter: Shows how much I know. I don't think my body can bend like that. Arms down. Arms down. Ow. That was pretty good. Is 40 years old too late to start? Dream big. Dream big. Reporter: Big dreams for her mean a second chance at a gold medal. This time in pyeongchang. What brought you back? My passion that I have for ski jumping and that feeling of flying again. I've loved it for so long, it didn't feel like I was ready to leave. Reporter: For "Nightline" I'm Matt Gutman in park city, Utah. Up next, it was meant to be
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