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Muscle contraction-invoke from outside the body

  1. Jun 30, 2013 #1

    Am not studying biology am engineer but iam just wondering if it is possible to make a muscle contract through external voltage maybe through some electrodes connected to some area on the skin.

  2. jcsd
  3. Jun 30, 2013 #2
    Yes, to a certain extent, but not usually as a coordinated muscle response. Coordinated actions can be produced by directly electrically stimulating the motor strip of the exposed cerebral cortex during surgery.
  4. Jun 30, 2013 #3
    Of course it's possible, haven't you seen this commercial?

    http://www.theflexbelt.com/?mcp=4140&KEYWORD=a b belt&gclid=CNrwreXvjLgCFU2CQgod61wAgQ

    Trust me, they work. My mom bought one some time ago and made me try it. It works so well it's creepy. So creepy, in fact, that I only tried it once. Of course, you could save some money and find out for yourself by sticking your finger in a light socket. But I wouldn't recommend that. Just take my word for it that it works.
  5. Jul 1, 2013 #4
    Thanks for your replies, but can anyone give more details how it works to make a muscle contract from outside source? what really happened?
  6. Jul 1, 2013 #5
    I generally don't like to reference Wiki articles for inquires like yours, but this article explains the complex and incompletely understood process about as clearly as any I was able to find. Essentially direct electrical stimulation of a muscle acts like a nerve action potential arriving at the junction of a nerve axon with muscle tissue (the neuromuscular junction). This opens voltage dependent calcium channels which in turn causes the release of the neurotransmitter acetylcholine. This results in an "end plate potential" which propagates through the muscle cell. The process ultimately leads to two proteins, actin and myosin sliding over each other by way of ATP dependent cross bridge activation causing muscle contraction.


    This second article is less detailed in terms of the process, but probably more clear if you don't have some general understanding of the subject.

    Last edited: Jul 1, 2013
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