By the way there XL Test Plus  is no such thing as a medial head. In anatomy medial refers to 'near the middle part of the body' while the correct term lateral refers to 'the outer part of the body.' The terms are commonly confused and understandable but they are in fact opposites not synonyms. Terminology is not the only thing that is misunderstood about shoulder training. Many people use shoulder programs completely unbalanced. Gundill  has noted that bodybuilders have frontal deltoids that are on average five times larger than sedentary people. 

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