NEW YORK: When Adeline Gray stepped on the wrestling mat in high school against a male competitor, she got his attention pretty quickly. She grabbed her opponent, and his 'eyes opened up like saucers, like 'holy cow, I've got to fight for my life,'' said her father, George. Gray is all business on the mat, with a 38-0 winning streak the past two years against women. She started wrestling at 6, first coached by her dad and uncle near Denver, Colorado. She grappled with the boys in youth leagues through high school. Now, the three-time world champion will attempt to win the first gold for US women's wrestling on Aug. 18 in Rio. 'She has the ability to stay focused when the lights are on,' George Gray said. 'She knows how to win.' Gray won the majority of her high school matches against boys at 130-140 pounds. Now she's coached by Terry Steiner, a former All-American wrestler at Iowa who leads the US women's national team. Women's wrestling was added at the 2004 Athens Games. When wrestling nearly got tossed out of the Olympics three years ago, increasing women's participation was among the improvements required by the IOC. Women were added to wrestling boards and female referees to the mat. Two more weight classes were added, bringing the total to six in Rio. Gray, a three-time world champion, has traveled to 22 countries for competitions in the last several years. She's spent eight years at the US Olympic training center in Colorado Springs, getting ready for the Japanese women. They won three of the four golds at the 2012 London Games, where Gray was an alternate. Here are some things to know about the 25-year-old Gray, who is ranked No. 1 at 75 kilograms (165 pounds). Early training She joined her uncle's wrestling club and started with tumbling and basic moves 'to see who had better balance.' She honed her wrestling technique and competitive skills around age 12, when she developed 'strength and skill and put that into a complete match,' she said. Gray says her mother Donna will attest that she was 'super-hyper' as a kid. Wrestling and playing soccer with her three younger sisters helped redirect her energy. 'I definitely think my parents had the option to medicate me to kind of calm me down, and they chose to put me in athletics,' she said. 'It helped me in school, it helped me in so many different areas of my life.' Grappling guys Gray was 16-16 against boys while attending Bear Creek High School her freshman year on the varsity team, where teammates knew her from growing up together on the mat. Her dad said she'd often trail 2-0 because the boys were faster at the takedown, but 'she'd always either reverse or get around and then get on top. She pinned a lot of boys.' Her family moved the next year and she went 20-10 at 135 pounds at Chatfield High School. Her junior year she was captain of the boys' team and finished 20-7. Occasionally, there was pushback from parents at other schools. 'Some of these boys played the gender card, 'I'm not going to wrestle her, we're not supposed to be hurting girls,'' George said. 'But guess what, I'd see him two weeks later at a different tournament wrestling a girl because he knew he could beat that girl.' While there were some forfeits, George says Adeline 'is where she is today because she wrestled the boys. It made her better.' 'I had my dad in my corner the whole time,' she said of the former wrestler and police officer. 'He really just gave me that freedom to go out there and be an athlete.' Olympic prep After winning the junior world title at 17, Gray moved to an Olympic development program at Northern Michigan University and finished high school in Marquette, Michigan. She recently earned a business degree through DeVry University. Gray will be joined in Rio by three teammates — Elena Pirozhkova (63 kg), Helen Maroulis (53 kg) and Hayley Augello (48 kg). The women wrestle two rounds of 3 minutes in freestyle, which allows for throws and hooking the legs. The men wrestle both Greco Roman, grappling from the waist up, and freestyle. Gator roll Gray is known for her arm bar and 'chicken wing' pins and the 'leg lace' move. That involves an arm lock around the ankles, crisscrossing them. 'Then a gator roll, you start turning,' her dad said. 'If they don't, they'll pop a knee or the pain is unbelievable, so you turn. That's two points.' Gray tries to dominate the opponent early in the match. 'You don't want to wait around to see people's best stuff,' she said. 'You want to hammer them with what you have and get off the mat.' Gaining Groud Women's wrestling is not an NCAA sport, but high school girls wrestling is gaining popularity in California, Washington, Texas, Florida and Hawaii, Gray said. What's the difference between wrestling boys and girls? '(Boys) don't have shoulders like Gumby,' she said. 'Girls get out of pinning holds that no boy would ever be able to get out of. Boys, their shoulders are so stiff, if you get the right leverage on a shoulder, they're going to go over and pin themselves.'