Although all Tai chi styles have the same objectives-opening and aligning the body, internal co-ordination, relaxation, settling the mind, chi development, internal power and self-defence-all styles have different areas of emphasis, and their own particular strong and weak points…
There are two main differences between the Wu and the Yang styles:
1) Soft versus hard energy:
The Yang style builds physical power, as it aims to develop internal energy that is half-hard, and half-soft, (or half Yang and half Yin), from the very start. It is particularly useful for martial purposes. However, it should only be practised by people in good health, as hard energy can aggravate illness or injury.
The Wu style is better for healing, as it promotes the development of soft internal energy (a healing energy for both mind and body). Hard energy comes later, produced by the soft energy. In other words, the Wu style starts with the production of Yin, which, when it reaches fullness, naturally produces Yang.
Soft energy is especially good for spinal or joint problems. It is effective for longevity, healing injuries and internal diseases, and making a weak constitution strong. Soft energy releases stress, and is therefore ideal for people with high-pressure and / or sedentary jobs.
2) The motions:
The Wu style is composed of compact motions, and compared to other Tai Chi styles, has relatively high stances. The high stances, and shorter steps, of the Wu style are better suited to Westerners, whose knees are generally not as flexible as those of most Orientals, primarily because we don’t squat anymore.
The Wu style has much less external motion than the other styles (up to a tenth of the size of typical Yang style movements.) The main emphasis is on moving internal energy and the muscles below the skin level. While this may not look as visually attractive, the small movements are easier for beginners to pick up. Later, the motions become more intricate and complex, and the subtlety of the style emerges.
In spite of its emphasis on healing the body and relaxing the mind, the Wu style is still good for fighting and pushing hands.