Active ROM is the motion of a joint that may be achieved by active muscle contraction. In addition to increasing strength, coordination between muscle groups is necessary because the guidance of assisting the patient through ROM is no longer provided.
Assisted active range of motion(AAROM) often happens in physical therapy, when you need to build up flexibility or strength in a particular body part. For example, you sit down and lift your leg up in front of you as far as you can.