Weakness is a lack of physical or muscle strength and the feeling that extra effort is required to move the arms, legs, or other muscles. If muscle weakness is the result of pain, the person may be able to make muscles work, but it will hurt.

Current as of: May 27, 2016

Author: Healthwise Staff

Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine & David Messenger, MD