Piezoelectric effect is the ability of some materials to convert change of pressure applied through that material into electricity. And vice versa, these materials spontaneously contract and expand with the frequency of an alternating electric current which passes through them. Up until recently it was commonly thought that only inorganic crystals posses piezoelectric properties.
Recent scientific experiments have confirmed that biological systems also posses this property. And very interestingly human bones present piezoelectric properties. If human bone is exposed to a continuous variable pressure, it creates an electric current going from joint to joint through the centre of the bone marrow. And it gets even better. This electric field stimulates bone growth.
Bone
The majority of bones consist of bone matrix that is inorganic and organic in nature. Hydroxyapatite, which is crystalline, forms the inorganic part of the bone matrix. On the other hand, Type I collagen is the organic part of the matrix. Hydroxyapatite has been discovered to be responsible for piezoelectricity in bones.
Origin of Piezoelectricity in Bones
When collagen molecules, consisting of charge carriers, are stressed, these charge carriers from the inside move to the surface of the specimen. This produces electric potential across the bone.
Bone Density and Piezoelectric Effect
The stress acting on the bone produces the piezoelectric effect. This effect, in turn, attracts bone-building cells (called osteoblasts) because of the formation of electrical dipoles. This subsequently deposits minerals--primarily calcium--on the stressed side of the bone. Hence, the piezoelectric effect increases bone density.
Significance for internal martial arts and Chi Kung
Internal martial arts and Chi kung exercises are supposed to be performed in slow continuous and smooth fashion. They are also supposed to be performed in synchronization with your breath and your heartbeat. Stepping should be performed without stomping. During weight transfer a leg goes from yin or empty leg with no weight to yang or full leg with all the weight.
Performing chi kung or internal martial arts exercises in this way creates continuous piezoelectric effect inside the bones, which produces continuous variable electric field with near constant frequency. This stimulates bone building and repair.
During the war in Yugoslavia experiments were performed on injured soldiers in orthopedic clinics in Belgrade. All the solders had complete bone fractures in their limbs, where parts of the bone had to be removed because they were shattered. They were bandaged with special bandages which contained small magnets aligned with the bone. The presence of magnets alone made bones to regrow with highly accelerated rate, leading to much quicker recovery. In some cases few inches of bone was regrown. Changing electric filed, such as the one created by continuous sinusoid pressure change in tai chi, generates magnetic filed in and around the bone. Magnetic field accelerates bone growth.
Many studies have been undertaken which prove that practicing chi kung increases bone density. Osteoporosis is unheard of in old tai chi practitioners. Again, modern science confirms ancient Taoist knowledge.
