When I evaluate a student, these are the posture items I consider, starting from the ground up:
Feet: I look at how the student has lined up his or her feet. If the feet are too close together or too far apart, then the student's playing balance is adversely affected. I demonstrate this unsettled balance to the student by playfully pushing them over from the side if the feet are too close together or backwards if the feet are too far apart. When in doubt, I ask a student to jump up and down a few times. How the student then lands on the feet is usually the perfectly balanced place. I ask students to allow for a "V" formation, and I adjust the feet when they are pointed inwards.
Knees: This is a problematic area. Many students tend to hyper-extend their knees backwards. This is not a good position, because the rest of the torso will be out of alignment. I ask the student to have soft knees. I use two exercises to help those students who have difficulty with the knees. One is to have them stand with locked knees as I hand them something a little heavier than a violin, like a small box. We talk about the pressure the student feels in the lower back and how unnatural it feels to stand like that when holding something heavy. Then I ask them to soften the knees and tuck under the pelvis as I hand them the heavier object again. This feels natural to the student. I find that although the student will now understand the correct posture, they still will have trouble remembering when they practice. So, my second trick is to place two books about 1-1.5" thick on the floor and ask the student to place the toes and upper ball of each foot on each book. Then when I ask the student to soften the knees, it feels completely easy and natural to do so and to retain this position throughout the practice. I figure that if the student practices like this on a regular basis, then the student will be creating and reinforcing the habit of softening the knees.
Thighs and Pelvis: After softening the knees, I ask the student to bring the thighs forward. Some students better understand when I ask them to tuck under their kitty cat tails. Bringing the thighs forward causes the pelvis to tilt and round upwards. Instead of swaying the back outwards, a pelvis that is tilted slightly upwards will help to curve the spine in a more desirable and natural way. In The Chi of Running by Danny Dreyer (http://www.chi running.com), the author talks about holding the pelvis in a way that doesn't spill out the runner's "chi." If the pelvis is tilted towards the back of the body, the pelvis cradle acts like a bowl that is tipped forward and over, allowing the chi to spill over and out of the body. If the pelvis is tilted upwards, the bowl retains the chi. Holding the pelvis in the "bowl" position helps to release the legs in a relaxed manner from the torso.
Hips and Torso: I next check the hips and torso to see that the hips are squared up and the torso is not twisted. When younger students are going through growth spurts, I often find that the body develops a slight twist in one direction or another. This is because the body does not grow evenly: the student could be lengthening 1/4" on one side and not the other; a slight twist will accommodate the additional length without the student tilting over to the side. I adjust for this and show parents how to watch for this posture issue and correct it. In teenagers or older students, I check that the students aren't putting more weight on one foot rather than the other and jutting out one hip.
Shoulders: I check that the shoulders are resting on top of the torso and rib cage. I check whether there is a lot of tension in the shoulders and upper back. I can touch a student lightly in those places and instantly feel the tension. It feels rock hard when the student is holding tension in various joint points of the body, although technically it is the muscles surrounding the joints that are tense and not the joints themselves. I will discuss in greater detail in future blog posts about tension in the shoulders, how to identify it, and how to ease it, but for now I just check to see that the shoulders look natural, that they are not curved forwards or upwards, and that the student is releasing any tension.
Neck and Head: The head is as heavy as a bowling ball and may weigh as much as 12-18 pounds. The head should float on the spinal column in a way that feels centered and balanced. The chin and neck should not jut forward; this often occurs because the violin is improperly held away from the neck of the body with a slight gap, caused either by the student placing his or her chin improperly on the chin rest or by the use of a pad on the violin that covers the instrument's bottom button (and thus creates space between the instrument and the student's neck). I will discuss at a later time about good placement of the head on the chin rest, but for now I'm just checking whether the head and neck are in alignment.
Arms, Elbows, and Hands: I check whether the arms and hands look natural. I will discuss in greater detail about the placement of the hands and fingers on the instrument, but for now I just check to see that everything looks relaxed and natural: the shoulders aren't pulling upwards to the student's ears, the elbows aren't higher than the student's hand (which I call chicken wings), and the wrists are generally flat and not kinked.
Joints: Students will hold tension in various muscles that surround the joints of the body, so I chack all of these as I travel from the top of the body back down towards the feet in reverse order. And just because I eliminate tension in one joint area doesn't mean that the tension completely disappears. The student may just move the tension to another joint area. For example, if I eliminate tension in the wrist, I find that the elbow, the shoulder, or the neck may become tense. For some students the search for and release of tension is an ongoing process.