When we move we often think or feel like we are moving in a single dimension, forward, backward, left or right. It is important to realize that movement of our body requires a symphony of coordinated movement between dozens of muscles working from various angles. It is extraordinarily beautiful when you break it down.
The shoulder and the hip are two of the most important joint complexes in the body because they connect our limbs to our torso. The muscles that hold the arm in the shoulder socket are fan shaped on the front (the pectoralis muscles), and on the back (the rotator cuff). The muscles that hold the leg into the hip socket are also fan shaped in the back and outside (the gluteus muscles and hamstrings) and the inside and front (the adductors or groin muscles and long part of the quad muscles).
Top notch therapists and chiropractors will evaluate an individual in motion as well as statically. They will look for asymmetries in the way the joints are moving. When exercising, it is important to be intentional when working the muscle groups from different angles. Traditional exercises tend to be much more linear and methodical rather than variable and adaptive. Life is all about adaptation, so exercises that maximize the use of different angles and require adaptive learning with provide the body with increased stability and function. So, look to vary the height of the pulley on the cable machine, change the angle of the incline and decline bench, do lunges in a fan like pattern as in the moving hands of a clock. An experienced personal trainer can help you to develop a program that encompasses the multi-directional approach to your training.