Expert answer
Hi, Joe. This is an excellent question, and as someone who tore her ACL playing soccer as a teenager and has had problems with her knee ever since, knee injury prevention is a topic that is very important to me. Anterior cruciate ligament (ACL) injuries are very common in young athletes, especially in women because of structural differences in their bodies, which tend to begin when they reach puberty.
A very interesting study by Kiani et al. in the January 11 issue of the Archives of Internal Medicine showed that a multifaceted, sports-specific (in this case, soccer) physical exercise program reduced knee injury by 77 percent. The program involved improved awareness of injury risk as well as promoting proper motion patterns and muscle strengthening to minimize injury. Interestingly, stretching was recommended only in cases of limited range of motion and not in athletes with loose joints.
The program, known as the HarmoKnee Preventive Training Program, comprises five phases, which I will summarize briefly.
1. Warm-up: This phase involves jogging, backward jogging on the toes, high-knee skipping and two zigzagging and sliding exercises.
2. Muscle activation: This phase involves four-second contractions of major muscle groups in the lower body, including calves, quadriceps, hamstrings, hip flexors, groin, and hip and lower back muscles to help athletes increase awareness of individual muscle groups.
3. Balance: These exercises, which require careful form -- including straight-line hip-knee-foot posture, shoulder-width apart, controlled landing on flexed knees, maintaining a low center of gravity, contraction of stomach and buttocks -- should be performed slowly. They include backward and forward, single- and double-leg jumps lasting approximately 30 seconds each.
4. Strength: This phase, which requires similar form to the balance phase, including walking lunges, hamstring curls and single-knee squats with toes raised.
5. Core stability: The final phase also encourages proper form and includes sit-ups, plank on elbows and toes, and bridging (an exercise where your hips are lifted toward the ceiling and the position is held).
Since the manual with instruction and photos for how to correctly perform the exercises is not available, my summary is meant as an outline for the key components of a comprehensive knee-injury prevention program. You may want to consider finding a coach or certified personal trainer who can help you develop a similar program and make sure your daughters use proper form.
There is also useful information and a few photos at the American Orthopaedic Society for Sports Medicine Web site and woman-specific information at the Women's Sports Foundation, a Web site founded by tennis legend Billie Jean King.
I hope this can point you in the right direction as far as building a solid program to help your daughters avoid knee injury. In addition, it is critical that they maintain a healthy weight to avoid placing excess strain on their knees.
