A positive exhalation pressure device (1) is described. The device comprising a housing (2) having an annular chamber (5), a chamber inlet (6) configured to permit air into the chamber, a chamber outlet (7) configured to permit air out of the chamber, and a mouthpiece (8) in fluid communication with the chamber inlet. A movable body (3) such as a ball is disposed in the housing within the annular chamber and configured to revolve around the annular chamber in response to flow of air through the chamber from the chamber inlet to the chamber outlet. The movable body is configured to at least partially block the chamber inlet and/or chamber outlet as it revolves around the annular chamber causing cyclical fluctuations in airflow resistance.
