A training aid stimulator comprising - a first skin electrode for making electrical contact to the body of a user, and - a second skin electrode for making electrical contact to the body of a user, - a charging module connected to a capacitor equivalent (135, C BODY , 139) , - a discharge switch module for controlling a feedback discharging of an electric charge, - a processor connected to the charging module for controlling the charging of the capacitor equivalent, to a predetermined first voltage level, wherein the processor further being connected to the discharge module for controlling a feedback discharge through the skin via the first and second electrode , wherein the training aid stimulator further comprises a voltage measurement module for measuring the level of charge of said capacitor equivalent and, wherein the processor is configured for keeping the training aid stimulator ready to discharge by repeatedly measuring the level of charge of said capacitance equivalent, and by providing a maintenance charging by activating the charging module when voltage of capacitor equivalent, is at or below a predetermined second voltage level, characterized in that the training aid stimulator further comprises a body impedance measurement module configured to measure the body resistance of the user using the training aid stimulator wherein the processor is configured to adapt the voltage of the feedback discharge based on the measured body resistance. - a first skin electrode for making electrical contact to the body of a user, and - a second skin electrode for making electrical contact to the body of a user, - a charging module connected to a capacitor equivalent (135, C BODY , 139) , - a discharge switch module for controlling a feedback discharging of an electric charge, - a processor connected to the charging module for controlling the charging of the capacitor equivalent, to a predetermined first voltage level, wherein the processor further being connected to the discharge module for controlling a feedback discharge through the skin via the first and second electrode , wherein the training aid stimulator further comprises a voltage measurement module for measuring the level of charge of said capacitor equivalent and, wherein the processor is configured for keeping the training aid stimulator ready to discharge by repeatedly measuring the level of charge of said capacitance equivalent, and by providing a maintenance charging by activating the charging module when voltage of capacitor equivalent, is at or below a predetermined second voltage level, characterized in that the training aid stimulator further comprises a body impedance measurement module configured to measure the body resistance of the user using the training aid stimulator wherein the processor is configured to adapt the voltage of the feedback discharge based on the measured body resistance. wherein the processor further being connected to the discharge module for controlling a feedback discharge through the skin via the first and second electrode , wherein the training aid stimulator further comprises a voltage measurement module for measuring the level of charge of said capacitor equivalent and, wherein the processor is configured for keeping the training aid stimulator ready to discharge by repeatedly measuring the level of charge of said capacitance equivalent, and by providing a maintenance charging by activating the charging module when voltage of capacitor equivalent, is at or below a predetermined second voltage level, characterized in that the training aid stimulator further comprises a body impedance measurement module configured to measure the body resistance of the user using the training aid stimulator wherein the processor is configured to adapt the voltage of the feedback discharge based on the measured body resistance. <EOS>