I read a Frederic Delavier’s book « Strength Training Anatomy » and I learned good stuff.
Standing with legs slightly apart. Your back straight with an arm your the back, Take your wrist with the other hand and pull slowly outwards and downwards to fell the stretch of the deltoid (rear and middle) and trapezius.
To stretch the neck does the same movement by slowly tilting your head on the opposite side of the shoulder stretched.
This variant allows you to stretch the deep and complex muscles around cervical vertebrae and scalene muscles and sternocleidomastoid muscle.
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