1. A training system that teaches an exercise using poses with a body, the training system comprising: a reproducing device; and a recording medium installed on the reproducing device, wherein the reproducing device is portable, and includes a display, a notifier, and a computer for controlling the display and the notifier, the recording medium is readable by the computer included in the reproducing device, and includes an elementary pose data storage that stores elementary pose data used to display a plurality of elementary poses on the display, a simple pose data storage that stores simple pose data corresponding to each elementary pose, and is used to display simple poses having a lower difficulty level than each corresponding elementary pose, and a breathing pattern image data storage that stores a plurality of breathing pattern image data corresponding to a plurality of timed breathing instructions to be notified by the notifier for each of the elementary poses and the simple poses, and the recording medium stores a program executed by the computer: causing the display to display an elementary pose based on the elementary pose data, and causing the notifier to notify on the display timed breathing instructions corresponding to the elementary pose based on the breathing pattern image data, when the elementary pose is displayed on the display, detecting a predetermined operation, when the predetermined operation is detected, reading out, from the simple pose data storage, simple pose data corresponding to a simple pose, which corresponds to the elementary pose being displayed on the display, and reading out, from the breathing pattern image data storage, breathing pattern image data corresponding to the read simple pose data, and causing the display to display the simple pose based on the read simple pose data, and in synchronization with the display of the simple pose data, causing the notifier to notify on the display timed breathing instructions corresponding to the simple pose based on the breathing pattern image data, to thereby teach an exercise using poses of the body.