Abstract: An audible push-up detector produces a sound when the device is compressed between the chest of a user and the underlying floor or surface, thus alerting an instructor or supervisor, as well as the user of the device, that the exercise has been performed properly. The device comprises a hollow, air filled flexible, pliable, resilient container having a reed valve or the like installed in one side. When the device is compressed, as between the chest and the underlying surface when a person is performing push-ups, air within the device pneumatically actuates the reed valve to produce a sound. Thus, the device is most useful in group exercise or physical training sessions, where a single supervisor or at most a relatively few supervisory personnel must monitor a large number of persons performing push-up exercises. The device includes a spacer disposed therebeneath, to position the pneumatic device at the proper height.