Many of the symptoms you describe are vague and could be due to a number of things including Provera. Some of the common side effects of this medication include weight gain, weak bones, headaches, fatigue, swelling. These symptoms could also be caused by a number of things such as thyroid problems.
Myofibrils are assembled of repeated structures called sarcomeres â the smallest functional unit of muscle fiber. Each sarcomere is formed of actin (called thin) and myosin (called thick) filaments arranged in a precise order and of protein complexes which support the filament structures.
1. muscle fiber-an elongated contractile cell that forms the muscles of the body. muscle cell, muscle fibre. fibre, fiber-any of several elongated, threadlike cells (especially a muscle fiber or a nerve fiber).