When people think of physical therapy, they often think of treatments for muscle and joint injuries; however, PTs treat nerve pathologies as well. Common nerve injuries include nerve root impingement from a herniated disc in the spine, nerve entrapment in the extremities, such as carpal tunnel syndrome and sciatica, and rapid stretch to a nerve that can occur in athletics or automobile accidents (“stinger”). These injuries to nerves can occur from repetitive overuse of joints and muscles, poor postural habits, or direct trauma. 
Peripheral nerves are complex structures that originate just outside the spinal column and then extend to all the muscles and organs throughout the body. The nerves often wind around bones or go through tunnels made by muscles and connective tissue. When a nerve is compressed by another structure in the body, or if a nerve is inflamed; it can produce numbness, tingling, or even sharp/shooting pain along the path of the nerve. This can be extremely debilitating and interfere with one’s daily function with even simple tasks. When a nerve is irritated in the above mentioned ways, the normal motion of the nerve is affected and the nerve can have increased tension placed upon it. Nerves are made of less elastic-type materials than muscles and cannot be stretched in the same way. When a nerve is tensioned from both ends at once (as with muscle stretching), one can actually damage or irritate the nerve further. Instead, the nerve can be mobilized in such a way that one end has tension while the other end has slack. Moving a nerve in this way is often referred to as “gliding” or “flossing,” and this method can greatly reduce nerve irritation and return a person to daily and recreational activities with reduced symptoms. Everyone has a pre-determined amount of tension throughout their nervous system, just as we all have a certain amount of muscle flexibility. However, this tension can be improved with manual physical therapy treatments and proper instruction in neural mobilization techniques. If you improve your neural tension, your overall flexibility can also improve, and this is an important component of overall fitness and health.
Here are a couple of ways you can feel your own neural tension:
Hamstring flexibility vs. sciatic nerve tension: while standing, place one heel on a chair with your knee straight. Stand up tall with a straight back and then gently lean your chest forward by hinging at the hips (don’t curve your spine). You should feel a stretch in the back of your thigh. If you feel the stretch extend down to the back of the knee or the calf, that is sciatic nerve tension. If you slightly bend your knee and you now only feel stretch in the thigh, that is your hamstring flexibility.
Bicep flexibility vs. median nerve tension: stand next to a wall or open doorway. With your thumb up, and your palm facing away from your body, place your hand behind you on the wall just below shoulder height. Keeping your hand on the wall, slowly rotate your trunk away from the wall and lean your head away from the wall. If you feel a stretch in the front of your elbow, forearm or wrist, you feel median nerve tension; if the stretch is only in your upper arm and chest, you feel your bicep and pectoral flexibility.