Yi Chin Ching "Muscle Tendon Changing"

:  This set of exercises focuses on the development of strength of the tendons and connective tissues. In Internal Martial Arts it is extremely important to condition the tendons and other connective tissues of the body, as much of the power in an internal punch is not generated from the arm itself but from whole body mechanics. The tendons become the weak point in the body chain since muscles receive more blood flow and recover and develop faster than connective tissue.
The exercises combine isokinetic and isometric principles, the range of motion is kept very small and because you are using the antagonist muscles (the muscles that oppose the chosen movement) to stabilize the movement the force is also constant over time. This provides more even development as the strength of resistance produced is only as strong as the body itself can produce.
Training Fundamentals: When practicing the muscle tendon changes they should be done on an every other day schedule to allow proper recovery time between sessions. The format for the exercises is broken down into three parts. Unless you are under the guidance of a teacher experienced with teaching these exercises who can gauge your level of development begin only with the first section and practice for at least a month before adding the other sections.
Flow is also important to these exercises, when practicing move directly from one to the next without stopping if possible. Many times exercises that share a common target area will follow each other to build on the common effect. 
Breathing and Focus:  Within each exercise a focus area is provided. When tension is applied the target area is where you should try to localize your efforts.  All stretches are preformed on the exhalation the inhalation should be used to relax and reposition the body if necessary. The movement itself should be isolated to no more than inch of change. Ideally the only visible change should be the application of tension to an outside observer.  The practitioner should observe all the given directions when applying force but use the antagonist muscles to provide resistance.
Development:  As stated above a period of one-month minimum should be observed practicing the first section of these exercises.  Taking additional time with these exercises is not a fault. Move at your own pace as these exercises target areas that may not be as strong depending on what your fitness regiment has been in the past.
Initially tension should start at thirty-percent of what you feel your maximal force can be.  This is done because the while your muscle may be able to produce a force greater than the connective tissues can handle. You will also need to develop the proper focus on the tissues and focusing on strength can be counterproductive.  The tension should be increased to at most seventy-five percent to protect from injuring the tendons.  Repetitions should also be built up, start with three then build to no more than ten.