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 (160, 161) for controlling a feedback discharging of an electric charge), and - 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 is connected to the discharge module (160, 161) for controlling a feedback discharge through the skin via the first and second electrode (135, 137), 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 capacitor equivalent, and by providing a maintenance charging by activating the charging module when the voltage of the capacitor equivalent is at or below a predetermined second voltage level, characterized in that the training aid stimulator is configured to - disconnect the voltage measurement module when a first voltage level is reached; - wait a predetermined period of time; - re-connect the measurement module, and provide maintenance charging if a measured voltage level is at or below a second voltage level. - 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 (160, 161) for controlling a feedback discharging of an electric charge), and - 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 is connected to the discharge module (160, 161) for controlling a feedback discharge through the skin via the first and second electrode (135, 137), 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 capacitor equivalent, and by providing a maintenance charging by activating the charging module when the voltage of the capacitor equivalent is at or below a predetermined second voltage level, characterized in that the training aid stimulator is configured to - disconnect the voltage measurement module when a first voltage level is reached; - wait a predetermined period of time; - re-connect the measurement module, and provide maintenance charging if a measured voltage level is at or below a second voltage level. - disconnect the voltage measurement module when a first voltage level is reached; - wait a predetermined period of time; - re-connect the measurement module, and provide maintenance charging if a measured voltage level is at or below a second voltage level.