Standing beneath a bouldering wall dotted with plastic holds of different shapes and sizes, Aubrey Lim carefully examines which route she wants to take.
Bouldering, unlike many other methods of climbing, doesn't use ropes or harnesses although athletes can use climbing shoes and hand chalk. Walls are typically no more than 20-feet tall and padded flooring helps prevent injuries from falls.
She pantomimes each hold with her chalk-covered hands, etching a path in her mind before committing to the challenge.
It's a normal routine for Lim, an 18-year-old Fresno native who has been climbing since she was 8 years old and will compete at the USA Climbing American Bouldering Series Youth Nationals in Colorado Springs this weekend.
"Climbing is second nature for me -- I grew up doing it," said Lim, a home-schooled senior who will graduate this spring and hopes to attend Cal Poly or UC Davis to study agriculture.
"I played soccer for a while, but chose to stick with climbing because it felt safer and it's not as cutthroat as other competitive sports."
In January, Lim finished fourth at the ABS 15 Junior Divisionals in Seattle, earning her a fourth trip to Nationals, where she is one of 38 climbers in her division.
The 5-foot-2, 115-pound climber who's ranked No. 4 in Northern California and 17th nationwide this year, reached the final round in 2013 and placed eighth in 2012 in the Youth-A division.
But Lim won't have all the time in the world to pantomime and figure out how to get from point A to point B when competing at Nationals.
At the three-day indoor competition -- qualifying Friday with semifinals Saturday and finals Sunday -- each climber in each round has four minutes to complete four designated "problems" or routes on the bouldering wall.
At the end of the round, climbers are judged on the number of completed problems and how well they solved them.
"You unlock it first, then execute it," Lim said. "As soon as I see the walls, I'll start climbing them in my mind and motion with my hands. I'll move my hands through the route and analyze it before I commit to it. There's no time to be indecisive. Indecisiveness can kill you."
In last year's finals, Lim hesitated and chose a route that had a large gap, requiring a jump from foothold to foothold.
"I had to jump sideways and it didn't work," she said. Lim fell to floor and finished 14th.
To sharpen her problem-solving skills, parents Jet and Dorie recently took Lim to climbing gyms in Sacramento, Stockton, San Francisco, Oakland and others to get more experience in different settings.
When not out of town, Lim trains at MetalMark Climbing & Fitness in central Fresno with climbing coach Clement Laksana.
With Laksana, Lim trained to strengthen her upper body and legs, and used interval training to improve her endurance and power.
"Competition climbers are forced to have the ability to problem solve and perform physically in an extremely short duration while keeping your nerves down," Laksana said. "It's not for everyone, but Aubrey definitely has the mental edge to compete."
Older brother Austin Lim, 19, has seen that toughness. On a recent outdoor climb in Bishop he said his sister pushed past pain to scale a boulder.
"Her hands were in no better shape than mine but she kept going. She wouldn't stop until she climbed it," said Austin Lim, who competed at the ABS Nationals in 2008, 2009, 2010 and 2011.
Said Lim: "I climb best when I commit."
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