Nerve Conduction Studies (NCS) and Electromyography (EMG)

NCS is used to measure the electrical activity and evaluate the function of the nerves.

EMG is a technique for evaluating and recording the electrical activity produced by your muscles when they are at rest and when they are being used.

Who needs Nerve conduction studies and EMG test?

Your doctor may order these tests if you have signs or symptoms that may indicate a nerve or muscle disorder. Such symptoms may include:


  • Tingling
  • Numbness
  • Muscle weakness
  • Muscle pain
How do you prepare for the test?
  • Wear loose, comfortable clothing that allows easy access to the test area.
  • Make sure your skin is clean.
  • Do not use lotions or creams before the test.
  • You can do any of your normal activities, like eating, driving, and exercising, before the tests.
Other precautions

Tell the neurophysiology lab personnel if you:

  • Have a pacemaker or any other electrical medical device.
  • Take blood-thinning medications.
  • Have a blood-clotting disorder.
After the tests
  • You do your normal activities after the tests.
  • There are no after-effects from the tests.
Test Duration

The tests usually take 15 to 60 minutes.