A combination of yoga and meditation which is popular amongst the Chinese population. One of the body movements invloves extending both arms out from the chest (with openned palms)which looks like a 'pushing' motion. In urban terms, it means 'pushing', or more appropriately, delegating own work to others. It is often a negative expression to indicate that a person has been avoiding responsibility by asking others to do his/her job.
He manage to leave work at 5pm sharp everyday because he is very good at tai chi-ing his work.