Back pain can occur in many different situations. As many as two out of five people will develop back pain in their lifetime.
Back pain is usually the result of muscle strain or spasm.
One of the most common areas is in the upper back in a muscle called the trapezius. Trapezius issues are often associated with spasm and strain in a surprising area: the front of the chest wall and the pectoralis muscles.
Those muscles in the chest, perhaps the ones you try to build up through weightlifting and bench pressing. When they’re very tight, they can actually pull around the shoulders causing a stooped shoulder position as well as pain. That pain can extend into the trapezius.
Source: cbslocal.com; Dr. Brian McDonough; June 3, 2014.