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Girls Can Jump: ACL Injury Prevention

Female skiers are more likely to tear an ACL than men. So we sent our knee-injured intern to the Boulder Center for Sports Medicine to find out why and to learn how to prevent and rehab knee injuries. Including her own.

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Females are four to six times more likely to damage the main ligaments in their knees. I remember the moment when I became one of those statistics. I was at Mt. Hood, in the park. I undershot the landing and hit the knuckle of the jump, my knee barely twisted inward. I didn’t even crash, but within minutes I found a cantaloupe-size ball of swelling around my right knee. I was in denial for days; at the time I thought you could only tear an ACL by hyperextension. This fall, I went to Boulder, Colorado’s Boulder Center for Sports Medicine to clarify my disillusions and get me on the road to recovery.

 The walls of the Boulder Center for Sports Medicine are lined with posters of professional runners and cyclists, but I also notice the “If you are active, you’re an athlete” sign in the entryway.

BCSM is always bustling with motivated athletes. Everyone who walks in looks fit, but plagued with an injury. I’m about to talk to my physical therapist, Larry Meyer, about my sore legs from our last appointment, which consisted of wall squats and one-legged balance exercises, when a tall, confident woman walks into the room. This is Christy Barth, the organizer of a female-specific training program for the prevention of knee catastrophes and someone who has devoted her life to improvements in sports medicine and athletics. Laid back and casual, she’s wearing khaki shorts, running shoes, and a t-shirt. I have some questions for her so she suggests we talk outside, where we can enjoy the sunshine.

 Barth, who has a B.S. in nutrition and exercise physiology and a masters in physical therapy, has skied for years and never torn an ACL. She recently started the Girls Can Jump program, which screens and trains female athletes to prevent knee injuries. “I have children now, and I’ve noticed the frequency of female ACL tears, and frankly, I wanted to develop a program so parents and their daughters don’t have to deal with going through a torn ACL experience.”

I wanted to know why women are more at risk for knee injuries. Barth and I sit down at a picnic table outside as she fires off considerations. “Proper assessments should look at female posture and body alignment, flexibility, muscle firing patterns, speed of muscle contractions, knee and leg asymmetry, possible quadriceps dominance, and core strength,” she says. Women tend to demonstrate knee alignment that lends itself to injury. Usually the knees rotate inward toward each other. When done with force (such as the knee rotating inward on the landing of a 30-foot table in the park), this is a primary method of severing the ACL. Women’s hips are wider, which displaces their knees into this knock-kneed position. In addition, ladies tend to use their hamstring muscles less efficiently than males and muscle contractions seem to happen slower, which can lead to injury. Barth says you can combat this by strengthening your legs through plyometrics and neuromuscular training, while conditioning the core.

Barth gets up, and with her legs shoulder width apart, she jumps, landing with her knees knocking together on impact. “We want to start by training the muscles in the legs to not land in this position, which is a tedious process. It involves a lot of repetition,” she says, while jumping again, this time landing solidly with both knees facing forward and inline with the feet. “It’s sometimes as simple as doing this over and over. If a girl can neuromuscularly train her legs to land like this, she will be preventing an ACL tear.”

Then there is strength. Female athletes need to work on explosive movements, involving power, strength, and speed. “Plyometrics such as single leg hops, and forward and backward legs hops over cones, completed with focus on the critical execution of landing correctly, can significantly increase the stabilization of the knee,” explains Barth as she demonstrates techniques. We also talk about walking lunges for quad strength, toe raises for balance and calf conditioning, core strengthening, and backwards running for the hamstring development.

I crutched away thankful I was in the care of a prominent facility, thinking that tearing my ACL may have spurred the best ski-training program I have ever tried. If you’re in Boulder, check out the Girls Can Jump program: Screenings start at $90 and include a 45-minute session with a physical therapist. If you’re anywhere else, most sports medicine and orthopedic centers offer similar programs nationwide.

Check out a gallery of photos from Michelle Parker’s ACL rehab routine.