A recent study examined the sit-to-stand movement of Alexander Technique practitioners as compared to healthy adult control subjects, revealing several significant differences.

The study, “Prolonged weight-shift and altered spinal coordination during sit-to-stand in practitioners of the Alexander Technique,” involved 15 Alexander Technique teachers and 14 healthy adult control subjects, who were recruited to match the age, height and weight of the Alexander Technique teachers.

During the research, each subject was instructed to sit on an adjustable height backless chair, with his or her feet resting on a custom-built force plate. Participants were told to stand up “as smoothly as possible, without using momentum.”

“This instruction aimed to encourage controls to mimic the gradual [Alexander Technique] weight shift,” state the study’s authors, “in order to understand whether it is simply a ‘choice’ of how to move or is difficult to perform, perhaps reflecting a more fundamental aspect of coordination.”

Additionally, the subjects were instructed to start from sitting upright and keep their arms crossed in front of their body. Each participant stood up at his or her own pace a total of five times.
The researchers collected kinematics, the detailed motions of each subject, using a seven-camera passive marker system, with markers placed bilaterally at the same key points on each subject’s body.

These points were the lateral orbital margin, tragus of the ear, posterior superior iliac spine, greater trochanter, lateral knee epicondyle, 3 centimeters proximal to the ankle joint along the fibula, lateral posterior calcaneus and the head of the first metatarsal, as well as the spinal processes of C7, T4, T7, T10, L1, L4 and the midpoint of the sacral crest.

Analyzing the details of the sit-to-stand motions of each participant, researchers discovered significant differences between the coordination of the Alexander Technique practitioners as compared to the control subjects.

“[Alexander Technique] teachers shifted their weight continuously as the trunk inclined forward, rather than at a more specific trunk angle,” state the study’s authors. “The continuous strategy indicates that [Alexander Technique] teachers simultaneously generate anti-gravity leg-extensor movements while soling the balance problem—bringing the center-of-mass forward over the feet.”

In contrast, subjects in the control group used a “sequential strategy” for the sit-to-stand motion, first bringing the trunk forward and then shifting their weight. These control subjects appeared to use greater hip flexor movements in order to stand.

“We hypothesize that decreased leg stiffness and increased power transmission through the spine [among Alexander Technique teachers] enable this continuous [sit-to-stand] strategy,” state the study’s authors. “Further studies are necessary to understand whether features of [Alexander Technique sit-to-stand] coordination are beneficial, from a performance or clinical standpoint, and whether they generalize to other motor behaviors, particularly those not explicitly practiced in [Alexander Technique].”

Authors: Timothy W. Cacciatore, Victor S. Gurfinkel, Fay B. Horak and Brian L. Day.

Sources: Neurological Sciences Institute, Oregon Health & Science University, Beaverton, Oregon; and UCL Institute of Neurology, Queen Square, London, United Kingdom. Originally published in Gait & Posture (2011).

Comments

comments