How Tai Chi Strengthens Bones?
Wolff’s law, developed by the German anatomist and surgeon Julius Wolff (1836–1902) in the 19th century, states that bone in a healthy person or animal will adapt to the loads under which it is placed.If loading on a particular bone increases, the bone will remodel itself over time to become stronger to resist that sort of loading.
So how dopes Tai Chi help? The controlled stepping involved in the Tai Chi form and footwork exercises means that for a period of time all the weight is placed through the standing leg. This means the leg muscles are fully engaged and compress on the bones of the leg and this creates the load discussed by Wolff. It is only through the slow movement that you can place the full load on the leg when it is bent and supports you full body weight.
While doing this you need to be in skeletal alignement because the standing leg needs to be able to support the whole body weight safely through the joints. When you move faster the body uses momentum to help it move and thus avoids placing your full weight through the standing leg and hence there is no load on the bone and Wolff’s law cannot operate.
So every time you are doing Tai Chi footwork and stepping you should feel the muscles and weight compressing the bones in the leg which is important in strengthening the bones of the leg. Developing stronger bones is critical to long term mobility in life.