I read a Frederic Delavier’s book « Strength Training Anatomy » and there is good stuff.
Sit on the machine with your torso on the backrest. With your arms outstretched takes the handles :
Inspire and spread your arms to straighten your shoulder blades at the end of movement.
This exercise works your posterior deltoid, infraspinatus and teres minor muscle. And at the end of the movement when you shoulder blades are tightened, it works your shoulder blades, trapezius and rhomboids.
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