From a physical point of view, there is the practice of contracting and stretching, which enables a man to bring out his inner vitality, whereas relaxation is a contrary action. Energy is either brought on to the outer plane or energy is put to rest in its natural, normal condition. When a person lifts something heavy, does something with determination, he charges his physical body with the energy which is within. It then expresses itself through his muscles and nerves. When a person is asleep the energy is put to rest. This energy is most valuable and precious; when it is used outwardly it brings external benefits and when it is used inwardly it brings about inner attainments.