Your muscles may feel weak when you have pain, but you should still have a normal range of movement. Brief periods of muscle weakness may be common after a strenuous workout. This type of muscle weakness usually means you have overexerted, and it is not a cause for concern as long as you can move and function normally in your daily activities.

True muscle weakness that occurs in one area of your body with a loss of function, even for a few minutes, is a medical emergency. It may be caused by decreased blood flow to the brain. Causes of decreased blood flow to the brain include:

• A transient ischemic attack (TIA) which results in a brief and temporary loss of function.
• A stroke which results in a progressive and permanent loss of function. Call 911 or other emergency services immediately if you suspect a stroke is occurring.