Manual muscle testing is the most popular way to test strength. Your physical therapist will push on your body in specific directions while you resist the pressure. A score or grade is then assigned, depending on how much you were able to resist the pressure. Strength is measured on a five-point scale:

• 0/5. A 0/5 score means that you are unable to create any visible or noticeable contraction in a specific muscle. This occurs when a muscle is paralyzed, such as after a stroke, spinal cord injury, or cervical or lumbar radiculopathy. Sometimes pain can prevent a muscle from contracting at all.
• 1/5. A grade of 1/5 occurs when muscle contraction is noted but no movement occurs. The muscle is not strong enough to lift the particular body part against gravity or move it when in a gravity-reduced position. A small flicker of muscle contraction may be palpated, or felt, during testing.
• 2/5. This muscle-strength grade is assigned when your muscle can contract but cannot move the body part fully against gravity. When gravity is reduced or eliminated during a change in body position, the muscle is able to move the body part through its full range of motion.
• 3/5. A 3/5 grade means that you are able to fully contract your muscle and move your body part through its full range of motion against the force of gravity. But when resistance is applied, the muscle is unable to maintain the contraction
• 4/5. A 4/5 grade indicates that the muscle yields to maximum resistance. The muscle is able to contract and provide some resistance, but when your physical therapist presses on the body part, the muscle is unable to maintain the contraction.
• 5/5. This means the muscle is functioning normally and is able to maintain its position even when maximum resistance is applied.