The effects of an electric shock on the human body

A shock can cause muscle spasms

Muscles are stimulated by electricity. The effect depends on the intensity of the current and the type of muscle it travels through.

We’ve all felt a buzzing or tingling sensation that doesn’t cause injury. That’s the effect of a current as low as 0.25 milliamperes (mA) entering the body.

When a current above 10 mA travels through flexor muscles, such as the ones in our forearms that close the fingers, it causes a sustained contraction. The victim may be unable to let go of the source of the current, making the duration of the contact longer and increasing the severity of the shock.

When a current above 10 mA travels through extensor muscles, it causes a violent spasm. If the muscles affected are the hip extensors that lengthen the limbs away from the body, the victim may be propelled, sometimes many metres away!

Muscles, ligaments and tendons may tear as a result of the sudden contraction caused by an electric shock. Tissue can also be burned if the shock is lasting or the current is high.