Entering the pose from the plow (halasana) is more demanding on the extensors of the spine, especially the thoracic spine, because they are in an elongated position before contracting. Entering from the bridge pose (setu bandhasana) is more demanding on the extensors of the shoulder joints and the flexors of the spine (the psoas and abdominal muscles).

From the perspective of the muscles of the spine and abdomen, being in the pose is less challenging than getting into it. However, remaining in the pose is more challenging for the muscles of the scapulae, because they are bearing the static load of the body while either contracting or lengthening.

To truly be a shoulder stand the muscles that adduct downwardly rotates, and elevate the scapulae must be strong enough to take the weight of the entire body. If they are not, and the shoulders spread apart, the weight falls too much on the upper thoracic and cervical spine.