Method for the electrical stimulation of a group of muscles in order to improve their appearance, and apparatus for carrying out the method

Portable apparatus for electrical stimulation of a group of muscles comprising:

• at least one storage battery,
• at least one pair of electrodes for application to the group of muscles, and
• circuit means connected to the at least one battery and to the at least one pair of electrodes to output a voltage of predetermined characteristics to the at least one pair of electrodes;
• wherein the circuit means comprise voltage-booster circuit means connected to the at least one battery for boosting the voltage,
• bridge circuit means comprising a plurality of electronic switches having control inputs, said electronic switches being connected to the voltage-booster circuit means and connected to the at least one pair of electrodes for providing the voltage to the at least one pair of electrodes;
• and
• piloting circuit means connected to the control inputs of the electronic switches to pilot the electronic switches so that, in operation, a symmetrical alternating voltage is applied cyclically between the at least one pair of electrodes for time periods of equal duration separated by intervals of predetermined equal duration;
• the alternating voltage in each of the time periods having periodic behaviour which is symmetrical in consecutive half periods, with pulses of equal duration and alternating polarity separated by intervals of equal duration.