Climbers stress the knees, especially when heel hooking, knee barring, and high stepping, or taking bouldering falls — in fact, a fall from five feet can tear an ACL just as easily as one from 20, especially onto an uneven surface. Like any other connective-tissue structure, the ACL typically benefits from healthy, repetitive use (read on), while a de-conditioned ACL is akin to leaving your rope in the sun for weeks. In fact, primate surgery has revealed that casting a limb for four weeks results in serious ACL weakness, from which it takes a year to recover!
So while surgeons all too often focus on reconstruction, it’s possible to prevent tears with proper nutrition, conditioning, and strength building. Here, some pointers before we move into specific exercises:
Stay Active. While biking won’t strengthen the ACL much, running on fl at and slightly declining grades can. Also helpful is using a leg-press machine into near-terminal extension, as well as cross-country skiing, with its forward propulsion from the nearly fully extended knee.
Avoid “Pro-Infl mmatory” Nutrition. Junk food, soda, hamburgers, etc. can tip your biochemical balance toward chronic inflammation, which damages cells and connective tissue. By shirking on fruits, vegetables, fish, lean meats, and fresh, unprocessed foods, you deprive yourself of key tendon and ligament nutrients (see Tech Tips: Training, No. 277).
Protect Your Meniscus. Prevention of meniscal injuries requires first and foremost an intact ACL. Sports nutrition, including cartilage nutrients, can stimulate meniscal strength over time. In Asian and African societies, where squatting is a daily habit, the meniscus’ posterior part is often engaged healthily. In Western societies, since we rarely fl ex this zone — the most frequently torn — it can get “soggy” (the so-called grade 2 MRI signal), which often evolves to significant meniscal tearing. Thus, it’s important to fully mobilize your knee, including maximum flexion. For climbers, this means warming up, cross-training, cardio, strength training, maintaining a normal body-mass index, and full joint mobilization (including full-squatting activities like yoga).
Learn to Land. When falling while bouldering, our instinct is to straighten our legs — but this extension makes the knees vulnerable. To absorb the shock, fall like a cat, with knees bent.
Three Exercises That Protect Your Knees
Note: Ramp up gradually — building connective tissue can take two years.
1. Hamstring Curl on a Physioball
How: Lie on your back with heels on the ball, knees straight. Tighten your abdominals and bridge your hips up, and then bend your knees to roll the ball toward you. Try two sets of eight reps with good form; work up to three sets of 15. Advanced challenge: single leg atop the ball!
Why: The ACL prevents forward movement of the tibia. Your hamstrings assist in preventing that motion (particularly in this exercise).
2. Floor Touches
How: Stand on one foot with your knee slightly bent. With the opposite hand, touch the ground outside your standing foot. Keep your back straight. Repeat on the other leg. If tight hamstrings restrict your reach (and your lower back rounds), bend your knee more and reach only halfway. Begin with two sets of 12 slow, controlled reps, and work up to holding a three-to-10-pound weight in the hand reaching the fl oor. Advanced options: reach to the front, then inside your standing foot.
Why: Multi-joint proprioception and eccentric hip control. This exercise enhances the body’s positional awareness, to improve protective reflexes, and strengthens the hip muscles that maintain knee alignment.
3. Sidestepping with a Theraband
How: Place both feet atop a Theraband and hold opposite handles, with your arms crossed. Slightly bend your hips and knees, and then step left with your left foot, stretching the band. Lift (don’t drag) the right foot, and then step it left to narrow your stance slightly, keeping your feet greater than hip width apart — use core muscles to steady your shoulders, with your feet forward. Begin with 15 to 30 steps in each direction (depending on the band’s tension) and work up to 100.
Why: ACL injury can also occur when the knee is forced into a valgus (knock-kneed) position; your hip abductors and external rotators can minimize this vulnerability. Traditional exercises and day-to-day activities don’t strengthen these muscles, making the ACL injury-prone in certain climbing positions.
Warm-Ups for Rock-Jock ACLs
Since the ACL is a ligament (non-contractile tissue connecting bone to bone), it’s difficult to warm it up as you would a muscle. However, the muscles that cross your hip and knee actually protect the ligament, so prepping these promotes ACL health. Try the following before climbing: •10 lunges on each leg, to open your hips and warm up your legs •10 floor touches (exercise No. 2 above) •Single-leg balance on the ground for 20 seconds — close your eyes •Two 30-second quad stretches (hold your foot in your hand and bend your knee, with your heel touching your behind)
Based on research work by
Thomas Rosenburt, MD, orthopedic surgeon; and Stacy McCooey, MSPT, physical therapist. Illustration by Keith Svihovec