What you have to be aware while doing an exercise is breathing. Let slow movement of the body be along with breathing. When exhaling, the body tissues shrink, and when inhaling they become loose. Therefore, when exhaling, movements of shrinking the body, such as lowering arms and bending the body are good, on the other hand, when inhaling, movements of loosening the body, such as stretching the arms and spreading legs suitable.
The purpose of exercise is not strengthening muscle power unduly, but regulating qi circulation of the body by exchanging air outside (outside qi) and air inside (inside qi) well.
*This article is translated from "Yamai hitokuchi Memo" written by Shoji Kobayashi, 2005.