Electricity had not yet been discovered when they started doing fish treatments: during the era of Emperor Claudius they tried to treat children with paralysis by putting electrical fish (electrical catfish, electric ray and electric eel) into their baths. Their electrical organs functioning as a condenser charges and discharges in defense against a real or perceived attacker.
Later on it was also revealed, which type of fish is the most effective for a given problem e.g. they used the electric ray for headaches. This was the predecessor of shock treatment, a process developed by Scribonius Largus.
In 1720 Stephen Gray discovered that the human body is electrically- conductive. In the 18th century electrical treatments began to be consciously applied.
Experiment on the muscles of the nerves, first electrical stimulation of the muscles with the resulting muscle contractions; each of these procesess is coined by Galvani and Volta. The most significant step forward was Galvani’s discovery. He observed that the muscles of the frog prepared for the experiment started twitching every time the electric device discharged. In addition, he also observed twitches in the frog’s muscles when the nerves and muscles were connected to different types of metals.
This was later on further examined by Volta. He observed that when two metals come into contact one would get positively charged while the other negatively as long as they are in contact. Since the 1800s electricity was extensively used in medicine. Electric current, current density, treatment location and duration become subjects of scientific research. The next advance in applying the various form of electric current was the utilization of selective stimulation current to treat weak or paralyzed muscles.
The first high-frequency electric stimulation was coined by the French physicist Jacques D’Arsonval Nemec introduced medium frequency treatments. With these electric currents a medium frequency treatment was created, which reduced the unpleasant effect of the shock and at the same time made a deeper impact. Low-frequency treatments have an intensity of 0 to 1000 Hz. Some treatments were based on the 0 frequency Galvan electricity therapy (also called direct current), while others used a frequency of 1-1000 Hz for electric stimulation. Nowadays, however, such devices on the market function with a max. of 250 Hz.
Researchers of the 19th and 20th century (Weiss, Lapique) studied the characteristics of electricity produced by muscular movements. It was discovered that using electric stimulation the human body could develop long term resistance. The rheobase and chronaxie principles were introduced and became widely applied.
In the 1970s the Russian scientist Kots applied the Electric Muscle Stimulation (EMS) technology on elite athletes and achieved a 20% increase in his subjects’ muscle strength. By the end of the ‘70s, the results of these studies were introduced in the Western sports world as well.
Since the 1990s these electric machines were reduced in size and protocols were established for a more general use.