low-impact muscle stimulator

Used with care, this circuit can provide a small degree of stimulation for muscles. Two electrodes are fixed on the skin covering the muscle area. The distance between the electrodes has to be between 1 cm and about 5 cm. The circuit generates voltage pulses at an adjustable rate of between 0.6 Hz and 4 Hz. The output voltage level is also adjustable between 0 V and 250 V. The highest pulse energy supplied by the circuit is limited to a value of about 0.4 mJ, which is generally believed to be safe.