It is becoming increasingly obvious as data is collected that the anatomical differences (while they may be a factor in injury to the knee) is not anywhere near as important as training before girls are exposed to extreme changes in direction on the soccer field and basketball court (the two sports which are notorious for ACL injuries to the knee).
Hormonal differences play a part in the strength of the musculature that help prevent injuries. We can't change the hormonal difference between males and females, and there is nothing we can do about structural differences in the shape of the hip/leg angles. This is the same bottom line. Coaches of girls must deal with it, accept the genetic differences, and work intelligently with girls -- not in the same way we work with boys.
We have seen that lack of training with the knees sufficiently bent is one of the major contributors to ACL injuries with girls/women. None of the female athletes we have worked with over ten years ever had ACL problems. This includes the 100 best female hockey players in Minnesota for each of ten years.
In figure skating, girls may jump (and land) inappropriately because of the genetic differences in the shape of the hip/knee angles. Coaches must train them to jump correctly ... over and over and over. One major solution to this problem is thousands of jumps with good knee bend, soft landings using muscles to soften the landing, and always keeping the knee in line with the hip/foot plane, not bowed inward!
Recently I watched a video of the very instant in which a good female college soccer player tore her ACL. She was practicing sprinting and cutting much like a wide receiver cuts in football. She was wearing short shorts, so it was apparent her quadriceps were skinnier than her knees. She was under-trained and not ready for this task, but her sport requires it from day one in competition!
In hockey, skating requires deeper knee bend than running. Girls who are developed totally from competition (and not training) will get some good training in a position of good knee bend just from the games. But while this may help prevent ACL injuries, it is not adequate for skating (or injury prevention). Two foot jumps are an excellent way to develop the leg strength needed for hockey skating.
One-legged strength training is also essential. Girls, even more than boys, should do one-legged strength training from the time they first put on a pair of skates. I have seen this work -- without one incidence of knee injury with thousands of young girls.
by Jack Blatherwick & Laura Stamm © September, 2011