A method for indirectly assessing the gesture, posture or movement of a body part of a person includes transmitting an ultrasound signal into the soft tissue, particularly the muscle, of body part and manipulating the reflected ultrasound signal to obtain parameter data. The parameter data is compared to reference information to obtain gesture, posture or movement information for the body part. Apparatus includes an ultrasound transmitter and receiver for transmitting, a signal processor, and a processor for storing reference information and determining gesture, posture or movement information for the body part.