Very interesting blog by Burr Leonard on the Bar method and knees. Lots of benefits
Four million years ago, our ancestors stood up and walked on two legs. Now our two knees, which are the body's largest joints, do the job that four knees used to do and they help keep us in balance, which is an issue when you're more vertical than horizontal. Our knees need all the muscles around them to be as strong and balanced as possible.
By systematically strengthening all three muscle groups that run through the knee - the calf muscle, the quads, and the hamstrings - Bar Method students keep it strong and pain free, which may be especially important for runners or participants in other high impact sports. Here's part of a blog from JaMarcus Russell, an American football quarterback, that I happened to run across:
"My current fitness obsession is The Bar Method. Check out Burr Leonard’s Exercise blog at http://blog.barmethod.com/. I have Burr’s two CDs and do the workouts at home. At one point I plan to sign up for classes too – the studio is comfortably close to the Embarcadero Bart station in San Francisco. The effect on my abs and lower back is astonishing, and my genetically weak knees do not bother me anymore." (Click here to read JaMarcus Russell's his entire blog.)
Even if you are not a serious athlete, the health of your knees is important. Knees carry the weight of most of our body with every step we take. Keeping them strong and youthful requires a prretty simple formula: strengthen and balance the muscle groups that extend across the knee joint.
The long calf muscle (the "gastrocnemius") is the first of three that intersect in the knee joint. You can see them toward the bottom of the picture to the left. This muscle enables us to come up onto the balls of our feet in what could be thought of as a "high heels" position. The great thing when it comes to knee stabilization is that the calf muscles extend across the back of our knees, thereby helping to hold them aligned and straight.
If you have an ACL (anterior cruciate ligament) injury, the gastrocnemius can stabilize the back of the knee inits place. This is why physical therapists give calf strengthening exercises to their patients with ACL injuries. The Bar Method’s starts its leg-exercises with heel lifts for this reason.
Above the knee on the back of the body are the hamstrings. The picture above shows this group of muscles (the biceps femoris, semitendinosus, and the semimembranosus.) The Bar Method is know for it's “seat-work,” which is really a series of exercises for the backs of your upper legs including the glutes. These exercises target your hamstrings, the third major muscle group that extends across our knees. Feel those kinds of sharp cords that run across the backs of your knees. Those are your hamstring tendons. When your hamstrings are strong, they help hold your knees in place. When these muscles aren’t toned, our knees get less support. A side benefit of strong hamstrings is the beautiful slightly rounded shape of the back of fit thighs of toned hamstrings.
The quads are the muscles in the fronts of our thigh and happen to be our bodies’ largest muscle group. The quads extend across the front of our knee. The intense, non-impact plies, little knee bends where the muscles stay engaged that we do in a Bar Method class, are tremendously effective to strengthen and balance the quads. The Bar Method’s knee bends are safe because students do them while bringing their heels up off the floor, thereby engaging the calf muscles to lock the knee in place.
Every Bar Method class includes at least three different sets of these plies with the quads at slightly different angles. These multiple positions assure that the quads get worked evenly. The four 
This is the fourth in the series of blogs on special challenges we humans face due to our evolutionary journey from four legged creatures to bipeds. Shoulders, backs, and knees changed radically as we stood up, walked, and used our arms to reach over our heads. We can stay supple and healthy by producing and toning muscle around these especially vulnerable areas.
