Last Updated on 5 October 2020 by Ray Plumlee
Electrical muscular stimulation or neuromuscular electrical stimulation is a technique in which muscles are contracted by the use of electrical stimulation that is applied with the use of electrodes.
WHAT IS ITS PURPOSE? AND HOW DOES IT WORK?
It is a modern technique that is used in electrotherapy during the rehabilitation protocols used for treating weak muscles. It is used in the strengthening of weak muscles. It works on a simple theory. As in one’s body physiology, in order to bring a muscle to contract and perform a movement, our brain has to send the specific message via nerves to the muscle. This message is sent in the form of electrical impulses. But when a person is suffering from some neurological problems, the nerves get weak and are unable to deliver the message to the targeted muscle. Hence, with the use of external electrical stimulation, the weak muscles are contracted to avoid further atrophy and to generate the lost pattern (this phenomenon is also known as neuroplasticity).
DIFFERENT TYPES OF ELECTRICAL MUSCULAR STIMULATION:
- Transcutaneous electrical nerve stimulation (TENS)
Transcutaneous electrical nerve stimulation (TENS) is a therapy that uses low-voltage electrical current for pain relief. The electrodes are placed over the skin (of the part that has to be treated) that creates a tingling sensation along the pathway of the nerve. It results in the production of natural body painkillers that are called endorphins. It is usually applied for 30 minutes to 2 hours. It is used to strengthen muscles, increase tone, pain relief and produce a good soothing sensation.
Modes of TENS and their benefits:
- Conventional mode:
High frequency and low intensity electrical stimulation is used to stimulate Group II (Aß) afferent nerve fibers. As the Group II fibers are stimulated, this TENS mode achieves analgesia primarily by spinal segmental mechanisms, i.e. pain gate theory. Pain is relieved for a short period of time.
- Acupuncture-like TENS:
Low frequency and high intensity electrical stimulation is used to stimulate Group III (Aδ) and IV (C) nociceptive fibers and small motor fibers. It is usually placed on the skin over the affected part. It works on the release of endogenous opioids via the descending pain suppression system. Pain is relieved for a moderate amount of time as compared to the previous one.
- Burst Train TENS:
The Burst Train mode of TENS is a relaxing type of TENS that creates a soothing massage impact as it is a mixture of Conventional and Acupuncture like TENS, so it has low-frequency current combined with high-frequency currents that come in the form of pulses.
- Brief, Intense TENS:
High frequency and long pulse duration current is used at the patient’s highest tolerable intensity for very short periods of time. This type is used for painful procedures such as skin damage, suture removal, etc.
- Continuous, Burst and Modulated Outputs:
These modes are a mixture of different modes and are used as per the comfort of a patient. The treatment is tailored according to the patient.
Uses Of ELECTRICAL MUSCULAR STIMULATION(EMS) :
- Uses in the field of physical therapy:
It is used in the rehabilitation program of a patient or a client who is suffering from any injury that results in muscular atrophy. It causes the contractions of a muscle group and thus keeps them active and in this way, it avoids disuse muscular atrophy in such patients.
- Weight loss:
Several forms of ELECTRICAL MUSCULAR STIMULATION (EMS) are used in order to warm up the muscles before the beginning of any exercise. Weight loss results when many muscle groups work together that actually results in the burning of several calories and thus, this leads to loss of extra fat from the body. So, with the use of electrical muscular stimulation (EMS), several muscular groups are made to contract that results in increased heart rate and increased respiratory efforts. Research suggests that people who tone up their muscles with Electrical Muscular Stimulation (EMS) are more likely to participate in athletic activities later.
- Muscular Re-education:
After an injury, the injured muscle may have spasm and loss of range of motion. To attain the normal tone and increase the range of motion, Electrical muscular stimulation (EMS) is used that trains the muscle. Plus it strengthens the link between a person’s brain and muscle.
- Prevention of pressure ulcers:
Pressure sores are basically a form of ulcer that develops on the areas that bear high pressure due to a prolonged posture. For instance, the areas that are more prone to pressure ulcers are buttocks in the wheelchair-bound individuals. Therefore, electrical muscular stimulation (EMS) is applied to the gluteus maximus muscle of such patients to avoid pressure sores on their buttocks.
- Pain relief:
As mentioned earlier, electrical muscular stimulation (EMS) causes pain relief by blocking pain transmissions. To understand this concept, just imagine that your brain gets the signal from your lower back nerve receptors that there is a problem in your back. Just when your brain is hearing this complaint, the electrical stimulations applied close to those pain receptors start to produce high noises and thus, your brain is unable to hear the problem of your low back pain receptors. As it hears nothing, hence you perceive no pain.
- Dangers of electrical muscular stimulation (EMS):
- Muscular tears:
If the electrical muscular stimulation (EMS) applied are of higher frequency than the tolerable frequency of the injured muscle or the muscle being trained, it may lead to muscular tears as the elastic limit of such muscles is very low and can be crossed very easily.
- Skin burns:
As electrical muscular stimulation (EMS) causes muscular contractions, which leads to the production of heat. Increased muscular activity leads to the generation of excessive heat, that may burn the skin.
- Electrical shock:
Just like the usual hazards that come when dealing with electrical currents, the use of electrical muscular stimulation (EMS) may lead to shock if the electrodes being used are faulty.