Since movement of the lymphatic fluid is not fueled by a pump, such as the heart, how do you think this liquid is propelled around the body? (hint: think back to some of the features of veins that blood fight back to the heart.

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.