The Strategy of Human Movement Control and Teaching Motor Skills in Norm and Pathology

The strategy used by the brain to organize human goal-directed movements is still debated. Here, I argue that without the knowledge of this strategy, teaching movement skills required in complex sports activities and for rehabilitation of motor disorders remains an art and can often result in inefficient techniques and misleading instructions. However, the leading joint hypothesis offers a solution to this problem. It suggests that the control strategy consists in rotation of a single ('leading') joint actively and using the biomechanical effect produced by the leading joint as the primary contributor to motion of the other ('trailing') joints. This "trailing joint control pattern" was found in a large variety of movement types. This pattern is simple even for seemingly complex movements, it can be easily verbalized, and it requires focusing attention during learning only on one or two movement elements at a time. The use of the trailing joint control strategy therefore allows development of better targeted techniques of motor learning and rehabilitation.