In this dissertation, different types of audio biofeedback (ABF) for core stabilization exercises using motion sensors are investigated. Core stabilization exercises are one of the strategies used in the treatment of low back pain. The Supine Bridge (SB) exercise was chosen as the focus for the investigation. The primary motion sensor used was a tri-axial accelerometer. Flex Sensors, Force Sensitive Resistors and multiple accelerometers were also used in other prototypes. The results of this dissertation, which include data from accelerometer, comments, process, reflections, and implementation of prototypes that generate 3 types of audio biofeedback, were gathered during 5 cycles of action research. In action research, the researcher conducts the research performing successive actions that attempt to reduce a specific problem in a real world environment. In this dissertation, the environment chosen was a place where a patient executes exercises and the problem identified is the difficulty of the patient to perform the exercises correctly. The action was the introduction of a wearable – StableBelt – which generates audio biofeedback based on the patient s movements during a core stabilization exercise. Different types of audio were investigated: instrumental music, piano and drums. The StableBelt was evaluated through 3 user tests. After a preliminary test with one participant, user tests with 5 and 8 participants were conducted. In the preliminary test, instrumental music was used and piano and drums in later tests. The last cycle of the action research was dedicated to the comfort of the StableBelt. During the investigation, physical therapists which research low back pain and physical therapists which use core stabilization exercises in their clinical practice were interviewed.