Chinese have long believed that practicing Taiji is good for one’s health. In the last 20 years or so, many western medical research studies have shown that there are many health benefits to Taiji, including: Lower blood pressure, increase immunity to shingles, provide relief to osteoarthritis, improve control of Type 2 diabetes, lower stress and reduce joint and back pain, reduce probability of getting Alzheimer’s disease. provide relief to depression, improve Parkinson disease, and generally improve health.  Although these conclusions are preliminary and need many more and larger studies to confirm, collectively they do provide impressive evidence that practicing Taiji does have health benefits. This article provides a high-level explanation why Taiji is good for health.
Our explanation is not down to the chemical level, because our understanding is far from that level of sophistication. Our explanation is based on several general principles that Taiji is based on:
- Relax the body and mind
- Engage in soft, slow movements
- Keep upper body straight
- Rotate waist
- Separate feet in the transverse direction
- Step down on the feet using a “cat step” approach
- Integrate with slow and lower abdominal breathing
- Mind leads form
The most fundamental and important principle of Taiji is to keep the body and mind relaxed. Relaxing the body and mind should reduce stress. We know from modern medicine that stress can create all kinds of health problems, thus following Taiji’s most important principle should reduce stress and therefore perhaps many kinds of health problems. Taiji as a martial art does not oppose an opponent’s force head-on, instead one supplements the opponent’s force with a small force either along the same direction or at a slight angle to the opponent’s direction. This supplementary force can deflect the opponent’s attack and at the same time makes use of the opponent’s momentum to get him off balance. Thus in practicing Taiji, one doesn’t have to be involved in strong, hard movements, instead one is involved in slow, soft rhythmic movements  that have no negative impact on the practitioner’s body, but at the same time the movements are aerobic. This increases flexibility, strength, and endurance, and especially helpful to joints.
Now we discuss those principles that govern the practitioner’s body position. In Taiji, the upper body is kept straight, as though there is a string with one end attached to the top of the practitioner’s head and the other end attached directly upward to the ceiling. This maintains good posture, and can avoid back problems. From a martial arts perspective, rotating the waist adds more power to a punch or kick. Rotating the waist also exercises the muscles on the back on both sides of the spinal column, thus strengthening those muscles and reducing back problems.
In practicing Taiji, how the feet are placed is extremely important. One almost never puts both feet on the same line, instead places the left foot about one shoulder-width to the left of the right foot. This increases stability because unless the center of gravity of the Taiji practitioner is outside of the two lines of support from the two feet, he will not fall. This increases balance and reduces the probability of falling which is common among senior citizens. When one steps with a foot, one uses the “cat step” approach, i.e, instead of stepping the toes and heel down simultaneously, one first steps down on the heel, and then steps down on the toes. This results in a sturdier step and again increases balance and stability.
Integration with breathing is very important in Taiji, although in an introductory course, proper breathing may not be discussed at all, or at least not in the first half of the course. One takes slow deep breaths, because that can bring in more oxygen and the oxygen remains in your body longer. Once one gets beyond an introductory course, one also practices lower abdominal breathing, instead of upper chest breathing. With lower abdominal breathing, the diaphragm moves up and down and the tummy expands and contracts. The movement of the lower abdomen results in massaging the internal organs that reside in our lower abdomen. Just like exercising muscles can strengthen those muscles, massaging the internal organs can strengthen those internal organs.
Finally, even though the mind is relaxed, it is not empty. The mind should be rid of extraneous thoughts, but it is not completely empty. Instead, the mind should lead the form, i.e., the mind should be visualizing the form that you are performing. Thus continuing to engage the mind keeps the mind sharp and avoids or at least delays the onslaught of Alzheimer disease.
By analyzing the fundamental principles of Taiji, one can gain some insights on why Taiji has health benefits
 See, e.g., the article “Health Benefits of Taiji” or the article “A Comprehensive Review of the Health Benefits of Qigong and Tai Chi.”
 In applying Taiji as a martial art, the movements are not necessarily slow, or soft. As a matter of fact, upon impact with the opponent’s body, the movement will be fast and with force.