In many countries, PAP machines are only available by prescription. A sleep study at an accredited sleep lab is usually necessary before treatment can start. This is because the pressure settings on the PAP machine must be tailored to a patient's treatment needs.
The pectoralis major muscle also performs internal rotation -- turning your arm in toward your body. This action, also called medial rotation, is important for reaching behind your back to tuck in your shirt and combing your hair on the opposite side of your head.
The pectoralis major is a thick, fan-shaped muscle, situated at the chest of the human body. It makes up the bulk of the chest muscles and lies under the breast. Below the pectoralis major is the pectoralis minor, a thin, triangular muscle. In sports as well as bodybuilding, the pectoral muscles may colloquially be referred to as pecs, pectoral muscle or chest muscle due to its being the larger and most superficial muscle in the chest area.