The document discusses the range of motion of muscle work, specifically focusing on the quadriceps and hamstrings muscles. It defines the full range of motion as the muscle changing from full stretch to maximal shortening. This full range is divided into the outer, middle, and inner ranges. It then provides details on the specific ranges of motion for the quadriceps and hamstrings muscles, and how weaknesses in certain ranges can impact functions like stair climbing or cause pain. Physiotherapy exercises often target strengthening the quadriceps muscle throughout its full range of motion.