Shoulder is a complex joint and so is its training schedule / program. Improve its strength and shape by working out optimum and with correct technique. 90% of the fitness freaks in the gym are noticed working out anterior and lateral muscles of shoulder, chest muscles, and biceps.
One needs to understand basic shoulder science. It is composed of anterior (front), lateral (outer-aspect) and posterior (back) group of muscles and it is equally important to strengthen the posterior (back) chain or the posterior muscles. According to the sports journal effective shoulder training needs an emphasis on Physiology and Biomechanics.
Recent study published in the American Journal of Sports Medicine suggests that significant improvement in shoulder strength was noted for tennis players who trained using resistance bands and cable machine.
The way exercises are done with free weights, resistance is applied only in vertical plane but resistance bands and cable machine helps you apply it over planes that are more functional.
It has been found that the muscle that experiences more time under tension experiences a greater degree of protein synthesis, repair and muscle regrowth.