A wearable device for the purpose of measuring expansion of the abdominal cavity as it relates to an end-user's breathing. The device is comprised of a belt with a sensing mechanism that interfaces with an electronics box. The electronics box communicates wirelessly with a phone application, which prompts the user to choose a variety of variables so that each breathing session is customized to their breathing needs. The belt measures the physical expansion of the user's abdomen in real-time, while the application offers real-time data displayed in various engaging graphical interfaces. The belt includes a first and second inextensible belt portion with an extensible belt portion disposed between. The belt includes a belt expansion measuring device configured to measure a length of the extensible belt portion and produce an electronic signal that corresponds to the length of the extensible belt portion and thereby the expansion of the user's abdomen. The proposed device not only monitors breathing, but actively assesses breathing in an objective manner so that users can learn to improve their abdominal breathing techniques.
