I perform at least one complete set of the Yi Jin Jing every single day. When done properly it relaxes all the joints and increases flexibility dramatically. However, it takes at least 90 days of daily practice before a. the habit really sets in, and b. the sense of relaxedness is properly sensed. It is, IMHO, definitely worth persevering with this practice.
“Not till your thoughts cease all their branching here and there, not till you abandon all thoughts of seeking for something, not till your mind is motionless as wood or stone, will you be on the right road to the Gate.”