The Outer Three Relationships (wai san he) for Qigong and Internal Martial Arts Close Combat
Box 3-23 Examples of the Outer Three Relationships
From Chapter 11 (copyrighted material) A Little More Advanced: The Outer Three Relationships
The wai san he (外三合), or “outer three relationships” (OTR), is one part of a pair of subdivisions of mind-body energetic principles known as the “six inner and outer relationships” (六內外合). More discussion of these relationships, with special attention to the other subdivision, nei san he (內 三 合), or “inner three relationships,” will be covered later. The OTR is a system of energetic relationships within the body that is applied to traditional Chinese medicine, Chinese internal martial arts, and multiple forms of Taoist energetic yoga.

Diagram 3-20 外 三 合
Wai San He “Outer Three Relationships”
The wai san he principles demonstrate how the elbow relates to the opposite knee, the wrist to the ankle, and the shoulder to the hip.

Figure 3-19 Wai San He -- Is Energetic Alignment illustrated in an old Manuscript?
Drawings of a Taoist yogi from a 1779 French manuscript suggest that the practitioner was paying attention to the alignment of his wrists.

Figure 3-21
Wai San He “Outer Three Relationships”
The Body’s Energy Matrix
From the viewpoint of the OTR, the body is understood as a network of interconnected, or “holographic,” relationships. As illustrated by the patterns featured in Diagrams 3-20 and 3-21, the OTR model demonstrates how some parts of the body have an energetic relationship with others. For example, as illustrated in the diagrams, when the right elbow is held just the right way in relation to the left knee, this “harmonizes,” or creates a strengthening relationship with, the left knee. The OTR principle is common in energetic yoga and Chinese internal martial arts, providing an important diagnostic and intervention technique that also applies to some systems of traditional Chinese medicine. An example of this can be found in acupuncture, where, in some therapeutic interventions, a needle might be placed in the left elbow as a means of treating an issue in the right knee. Sometimes, however, the OTR principles apply to the same side of the body. Drawing 3-22 is borrowed from a paper on the subject, authored by Dr. Henry McCann, published in the Journal of Chinese Medicine. [i]
[i] McCann, Henry, “A practical guide to Tung’s acupuncture,” Journal of Chinese medicine, February 2006

Diagram 3-22
The Outer Three or “Holographic” Relationships
This diagram is from a paper presented by Dr. Henry McCann,
Henry McCann, “A Practical Guide to Tung’s Acupuncture,” Journal of Chinese Medicine
From Theory to Personal Experience
As demonstrated via the video link included in Box 3-18, because of its signal-feedback attributes, energetic practices such as Chinese yoga and qigong can be vehicles for exploring the body's energetic relationships. In the context of the OTR, this exploration converts the practice from theoretical to personal experience and practical application. In terms of the biomechanics that apply to the martial arts, one representation of OTR principles has to do with the way a strike is timed with the landing of the foot. In this context, when performed correctly, it represents the perfectly timed and coordinated hand and foot movement, where the execution of a step and a strike are synchronized. This OTR-based synchronization is in contrast to the more common way of foot / hand timing, where the foot sets slightly ahead of a hand strike. A video example that demonstrates both body mechanics and energetic body matrix principles can be viewed at the link in Box 3-23.
Exploring the Meaning of Signal and OTR Resonance
Using a variation of signal and resonance training, it is possible to test one's own OTR. In this case, OTR practice involves observing changes in the body brought about by making subtle adjustments to one's body position, i.e., pertaining to foot and hand orientation, and their relationship to each other. Consider that with each posture in an energetic practice, such as t’ai-chi or yoga, when the person is sensitive and open enough, he or she can become aware of how very slight changes to the body reveal the ideal position for a particular movement. This is due to the fact that when an aspect of the body deviates slightly from the optimal, it manifests as a weaker overall energy profile of a particular movement or posture. As an example, when the shoulder is not in optimal alignment with the hip, this will have a weakening influence on the energy system of the entire body.