As a coach, one of the most common things I hear from new athletes is, “I have bad knees.” I’d say about 80% of new people walking in the door tell me this. Then I get to hear about how they can’t squat because of their bad knees. I will listen raptly to them and yet, there are only a few words I’m looking for, (“Surgery, TKA, torn ____”) Now, I don’t mean this harshly, but when someone has “bad knees,” it normally means they have just weak knees or they have never been taught to squat properly. So what is a “good” and a “bad” knee? And how can we take weak knees and make them better? And what is a good squat and can they help your knees?
What is a Knee?
The picture to the right is a healthy knee with all the proper ligaments and cartilage this joint should have. The knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). The knee is a modified hinge joint, which permits flexion and extension as well as slight internal and external rotation. It is often termed a compound joint having tibiofemoral and patellofemoral components.
A knee is a joint and therefore needs muscle stimulation to be moved. The muscles responsible for the movement of the knee joint belong to either the anterior, medial or posterior compartment of the thigh. The extensors generally belong to the anterior compartment and the flexors to the posterior. The two exceptions to this are gracilis, a flexor, which belongs to the medial compartment and sartorius, a flexor, in the anterior compartment.
Problems in the Knee
Some of the problems and issues that can be identified as knee pain is caused by trauma, misalignment, and degeneration as well as by conditions like arthritis. The most common knee disorder is generally known as patellofemoral syndrome. The majority of minor cases of knee pain can be treated at home with rest and ice but more serious injuries do require surgical care.
One form of patellofemoral syndrome involves a tissue-related problem that creates pressure and irritation in the knee between the patella and the trochlea, which causes pain. The second major class of knee disorder involves a tear, slippage, or dislocation that impairs the structural ability of the knee to balance the leg.
Patellofemoral Syndrome is sometimes referred to as runner’s knee, Chondromalacia patellae, Iliotibial band syndrome, and Plica syndrome. The most common symptom is vague pain around and behind the kneecap. This pain is usually initiated when load is put on the knee extensor mechanism, e.g. ascending or descending stairs or slopes, squatting, kneeling, cycling, running or prolonged sitting with flexed knees.
Treatment for Knee Pain
The majority of exercise programs intended to treat PFPS are designed to strengthen the quadriceps muscles. Emphasis during exercise may be placed on coordinated contraction of the medial and lateral parts of the quadriceps as well as of the hip adductor, hip abductor and gluteal muscles. Many exercise programs include stretches designed to improve lower limb flexibility.
A 2011 systematic review stated that evidence supports the use of quadriceps exercise for managing PFPS and that quadriceps strengthening is considered to be the “gold” standard treatment for patellofemoral pain syndrome. Quadriceps strengthening is commonly suggested because the quadriceps muscles help to stabilize the patella. Quadriceps weakness and quadriceps muscle imbalance may contribute to abnormal patellar tracking.
So did you catch that? Squats (an exercise that builds the muscles in your quads) are good for your knees!!
You Don’t Know Squat!
“Coach is yelling at me again to get lower. He knows I have bad knees and that I can’t squat that low.”
Well let me tell you that, squats are NOT a knee dependent movement. They are a hip movement and the knees just go along for the ride, WHEN you squat correctly. Hips are better protected joints than knees as they are completely surrounded by muscles. These also happen to be the same muscles that control the movement of the knee! Muscles that just so happen to get stronger when you squat correctly. So if your knees “are bad,” then you should squat parallel (or lower) more often to build up the muscles that protect the knees
A correct squat begins at the standing position with your feet slightly wider than shoulder width and toes pointed slightly out. (10-15 degrees) From there the athlete will bring their hips back and downward, as if to sit down on something, and lower until their hip crease is parallel to the ground. The heels remain on the ground with the weight in them and to stand the power is driven through the heels. The back and core remains tight and straight with no curve or arch. Chest and shoulders should be back and assist in keeping the back straight.
What Happens During A Full Squat
As the athlete sits back and down, the hamstrings and glutes act in synchrony to contract and control the descent. The quadriceps on the front of the thigh and the muscles in the core isometrically contract to help hold the athlete upright (because falling over during exercise is generally considered a bad thing to have happen). As they descend past the 45-degree mark, the quadriceps now have to lengthen in order to allow greater contraction (read: activation) of the hamstrings. This also enables increased dorsiflexion of the ankle (decrease in angle between shin and foot) as the tibia shifts forward to provide more stability. At the bottom of the squat, the muscles of the core and hamstrings are all maximally contracted to hold the position.
As the athlete begins the ascent, the hamstrings now become the stabilizers as they re-lengthen and the quadriceps now contract as the knees and hips extend in synchrony. The squat is a balance between the muscular recruitment of front (quads, anterior tibialis, abdominals, hip flexors) and back (glutes, hamstrings, erectors, calves). During the full squat all muscles operate in balance and work together to effect the desired movement.
What Happens During A Partial Squat
A partial squat allows for just that, a partial recruitment pattern of what a full-squat normally entails. Unfortunately muscle imbalance is guaranteed and the chance for injury is thus much higher.
If an athlete performs a partial squat, the athlete inhibits his hamstring recruitment by only going down partway. This forces the quadriceps to bear the brunt of the load early on, as their initial isometric contraction can’t relax from the stretch of descending deeper. Concurrently, the hamstring contribution to the exercise is very limited as hip extension is severely shortened. What typically happens here is the knees tend to “slide” forward, creating sheer forces within the knee joints. (read: trouble and knee pain) In a partial squat when muscular recruitment is minimal, the knees must bear the brunt of the load.
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 Patellofemoral pain syndrome (PFPS) is a syndrome characterized by knee pain ranging from severe to mild discomfort seemingly originating from the contact of the posterior surface of the patella the femur
The population most at risk from PFPS are runners, cyclists, basketball players and other sports participants. Onset can be gradual or the result of a single incident and is often caused by a change in training regime that includes dramatic increases in training time, distance or intensity, it can be compounded by worn or the wrong type of footwear. Symptoms include discomfort while sitting with bent knees or descending stairs and generalized knee pain. Treatment involves resting and physical therapy that includes stretching and strengthening exercises for the legs.