Joint Articulation in Terms of Injury Prevention
Part 2: The Knee
As a kid I played soccer and usually didn’t think twice about going in for the slide tackle, going foot to foot with someone twice my size or running head on colliding with other players. However, in the eyes of just about every child and adolescent as far as they are concerned they are superman/woman, unable to be injured and essentially invincible. However, as I have grown older I have learned that just being a beast and having no fear doesn’t mean that you can’t get seriously injured. And as I am sure you have all come to know as well, being injured is nowhere near any kind of fun. But good news for us weightlifters, there are many things we can do to prevent injuries!
The knee joint is problematic for many people and injuries to the knee can be career ending in any sport or aspects of athletics, bodybuilding included. However, since bodybuilding is not a contact sport the amount of injuries that the knee are greatly reduced, thank goodness. Before we go into full-fledged knee analysis during certain exercises lets first take a look at some basic anatomy of the knee. This will also make it more clear to you the mechanisms of injury that can occur at the knee as well as how exercises can benefit you by placing the joints in proper position.
The knee joint consists of the coming together of the femur and tibia bones. The patella is also active at the knee, however the patella is a sesmoid bone and is incased in the patellar tendon. However, for the duration of this article I want to focus on the main ligaments at the knee and between the tibia and femur. There are also menisci in the knee joint which help to combat the forces that are experienced at the knee and so the bones do not rub together, this would be painful.
The knee is relatively limited in the movements it is capable of simply due to the articulation of the tibia and femur in the way that they fit together. They only allow for some internal and external rotation but main exhibit flexion or extension. While us bodybuilders are usually primarily concerned with our muscles it is very important actually for us to begin to focus on the other aspects of our body. This includes the joints. Because if it weren’t for the joints we have we wouldn’t be able to move the weight like we do. That being said it is at the joint where most of the injuries and problems develop, name with ligaments and tendons as opposed to the actual muscle we are focusing on. With the knee this is very important because the knee, although it does not exhibit a large range of motion, it has some very, very powerful muscle acting on it and therefore is affected in a different way. The knee has lots of ligaments to protect the movements that it exhibits. I will not bore you with the intricate names but I will be happy to discuss that with you, if you are interested let me know. But the important part is that there are ligaments on both sides, the front the back and across the joint itself. In terms of bodybuilding the side ligaments are not at as high of risk for injury due to the fact that bodybuilding is a non-contact sport and hopefully that means you aren’t getting blows to the inner side and outer side of the knee at the joint itself. The ligaments on the front and back as well as the menisci, however, can be affected more easily.
Weightlifting has proven beneficial time and time again for many reasons I’m sure you can list rather quickly. A reason that you my not be as familiar with is the result of weightlifting on the connective tissues at the joints. Connective tissues are actually seen to be stronger in powerlifters and weightlifters than the average joe. This is because of the increased forces that they undergo due to being pulled extremely by muscles, they seem to adapt in some way to become stronger in order to be able to perform their duties better! It is important to note before discussing the squat that it is far more beneficial for the bodybuilder than harmful (that is when performed with proper form, and not when increased weight results in a reduction in technique or form).
That being said, the deep squat you would think is harmful to the ligaments at the knee joint. However, newer research has shown otherwise. Deep squatting actually results in the pressure being taken off of the ACL and PCL due to the nature of the angle when the knee is in a deep squat. Compressive forces are experienced during a deep squat, which actually places more stress on the menisci in the knee. Deep squats may also increase susceptibility to patellofemoral degeneration, again due to the deep nature of the squat and the knee undergoing increased amount of flexion. Furthermore, the studies conclude that one could argue that the parallel squat has the potential of causes more injury than the deep squat. The argument is made on the grounds that the most amount of shear force exhibited
by the knee is in the parallel position because of the articulation of the tibia and femur. However, the force that is experienced here, even in the parallel squat, is still only a little over half of what the knee can actually withstand before exhibiting any kind of plastic damage. The nature of the angle of the deep squat is actually seen to induce increased muscular adaptation at the knee and hip joint. Yes this is true but why? If you find yourself doing things without ever asking the question why, I challenge you to be more aware of all of your actions, not just in training alone, and go through life doing things for a known purpose instead of for reason unbeknownst to you.
Anyways, back to increased muscular development at the knee. By squatting deep, first of all the muscle is experiencing an extreme stretch at the bottom of the movement and is then forced to contract. Therefore, the actin and myosin overlap within in the muscle fibers themselves are at the optimal range. Most good exercises like the squat, incorporate a stretch within the exercise thus placing the joint at an optimal angle which thus results in an optimal range for actin and myosin overlap at the cellular level. With optimal overlap this means essentially the muscle can contract most efficiently.
So what’s the take home message? Squats are win, win for the knees. I cannot speak for other joints at this time because our focus here was strictly on the knee joint itself. But, if you want your quads and glutes to grow, your best bet will be to perform squats are some variation of the squat. As a side note, the trunk position in a squat especially the back, are essential for obtaining good form for a squat. I did not discuss overall squat form here, only that of the position of the knee. So, just because squats are awesome, doesn’t mean you should do them if you have underlying injuries that would be affected by loading the spine or anything else that a squat calls for. I feel the need to put some sort of disclaimer on all of these articles simply because I feel there will be the one person who reads tem and forgets all other things in life and goes straight out to do the exercise. So again I caution you when performing any exercise that is contraindicated to your own personal health.
Sources and Photos from:
http://www.nsca-lift.org/HotTopic/download/Squat%20Depth.pdf
http://www.sportsinjuryclinic.net/cybertherapist/kneeanatomy.php
http://saptstrength.com/wp-content/uploads/2011/12/arnold-squat-franco.jpg
http://www.datlof.com/8axamal/docs/marketing/jhu/je/index.htm
Subscribe to RxMuscle on Youtube
