Moreover, using transcranial magnetic stimulation (TMS) in humans, it has been found that the corticospinal excitability of particular hand muscles is modulated by the shoulder position; suggesting a flexible cortical drive to hand muscles depending on arm position [ 21].
The supraspinatus has a greater mechanical advantage vs the other tested muscles in the neutral arm position.
An example would be uncertainties that depend on the arm position or current muscle lengths.
It is known that persons with a lack of trunk muscle strength can compensate with the recruitment of shoulder and arm muscles [37,46,47]; therefore, the difference in arm position can have caused bias in these results.
The higher muscle activity in the present study could be explained by the difference in arm position between the studies.
Then change their arm position to above their head and prop it up again; this changes the fibers of each muscle area, go through the area again for a more detailed, deeper effect.
Kieffer-Olsen [23] observed four different arm positions in Southern Scandinavian during the Middle Ages: arm position A (AD 1100 1250), arm position B (AD 1250 1350), arm position C (AD 1350 1536) and arm position D (from AD 1536 onwards).
The right arm position was classified as "conditionally acceptable".
Arm position was not prescribed [ 18].
The stereotyped vm2 muscle arm structure indicates a specific guidance mechanism regulating the muscle arm extension.
