Begin by making a list of the muscles from the Top 20 that are used in each of this yoga pose. Remember that some of the Top 20 muscles may not be illustrated, but can still be used in these poses; you must include those in your answer.
Once you have made your list, answer the following question:
For each muscle in your Top 20 list, describe its role in the pose. For full credit, your description must include the joint that is affected by each muscle and the action of that muscle on that joint (remember, a muscleactionat a joint is the result of the force the muscle applies to the bones on opposite sides of the joint; movement is one possible result of this action).
For example, if the arm is held up parallel to the ground and then horizontally adducted so that it is pointing straight ahead, then the pectoralis majoris acting in horizontal adduction and flexion of the glenohumeral joint; the latissimus dorsiis acting in horizontal abduction of the glenohumeral joint to resist adduction; the deltoideusis acting in flexion and abduction of the glenohumeral joint.
The flexors of the GHJ are working against the force of gravity; the horizontal adductors are working to move the GHJ into the pose and to stabilize the joint against the actions of other muscles; and the horizontal abductors are working to stabilize the GHJ against further horizontal adduction.
When in doubt, ask yourself what would happen with the body in that pose if any of the Top 20 muscles were not acting.