The invention relates to a method and an apparatus for electrical stimulation of muscle tissue. Electrodes (12) of an electrode array (13) are activated in accordance with a sequence of activation patterns, each pattern defining a subset of the electrodes (12) to be activated, each subset consisting of at least one electrode (12), by providing an electrical muscle stimulation signal to the muscle tissue via the subset of electrodes (12). Alternately with said activating of electrodes (12), a response signal associated with the respective activation pattern is received from a sensor (30; 12). Optionally, at least one electrode (12) is then selected for stimulation, corresponding to a location determined as being suitable for stimulation, and the muscle tissue is stimulated. The process may be repeated in order to track the location suitable for stimulation in a dynamic situation. Optionally, the orientation of body part is estimated from the measured response signals.