You just can’t seem to figure out what is causing your pain in the back of leg while running. Sound familiar? You may be experiencing something called “neural tension.” It’s not just muscles that get tight; our nerves can also be susceptible to decreased movement.
Sciatic nerve irritation (“sciatica”) can sometimes be confused for hamstring tightness. The problem is doing a hamstring stretch is not going to help stretch our sciatic nerve; we need to “stretch” neural tissue differently. Today we will talk about what neural tension is, how it can affect your running, and what you can do to resolve it.
What is Neural Tension?
Nerves are encased in sheaths that protect the nerve as your body moves. For various reasons, the nerves may not be able to slide back and forth effectively within this casing. This can cause perceived tightness, pain, numbness, and/or tingling. Usually the symptoms occur in relatively predictable patterns, especially if muscle stretching or massage is not changing your back of the leg pain when running.
Why Does Neural Tension Happen?
Nerves get “pinched” or “stuck” at various places along the path of a nerve. Nerves originate off the spinal cord, both in the neck and low back, and travel down the arms and legs to innervate the muscles of the limbs. A nerve may be compressed right after it comes off the spinal cord or could be getting impinged further down the line. Neural tension symptoms occur in both the upper and lower extremities.
For example, if the sciatic nerve gets “pinched” by a structural issue or disc in the low back, it is called a “lumbar radiculopathy.” As the sciatic nerve travels down the back of the leg, it will pass through the piriformis muscle (in the buttock) in most people.
An irritated or tight pirformis muscle pressing on the sciatic nerve causes symptoms similar to lumbar radiculopathy. While both places of irritation cause “sciatica,” the location of the impingement is important to determine the best treatment for your specific situation.
What Can I Do To Prevent Neural Tension?
The specific positions your body assumes in your particular sport or activity may promote symptoms of neural tension. For example, in the upper extremity, the arm position a baseball pitcher uses for a throw is also a position of maximal nerve tension. This can cause nerve symptoms down the arm and into the hand. Similarly, neural tension in a runner can feel like “tight” hamstrings or calves and may impede a runner’s ability to straighten his or her leg during a forward stride.
There are several things you can do to decrease the likelihood you will experience neural tension symptoms while running:
- Make sure your shoes are appropriately supportive for your specific running pattern.
- Do regular foam rolling/flexibility routines for the glutes, hamstrings, quads, and hips to maintain ideal muscle length and soft tissue quality.
- Address any muscle imbalances by incorporating lower body weight exercises, like squats and deadlifts, in your routine.
I Think I Have Neural Tension: What Do I Do?
It is important once again to determine if and where your sciatic nerve isn’t moving well. There are specific tests designed to do just that.
The Slump Test
The slump test is one way to determine if your sciatic nerve irritation is coming from your low back. First, you need to sit straight up with your legs out in front of you. Then, slouch forward so your back is rounded and bring your chin to your chest. Next, try to pull your toes towards your shins while keeping your legs straight to see if this recreates your symptoms. Some stretching in the back of your leg is normal.
Figure 1. Slump Test set-up.
The Straight Leg Raise Test
The straight leg raise test is another test used to determine if your sciatic nerve is irritated. Use a strap or belt to raise your leg straight up into the air and then pull your toes back towards your shins. If this doesn’t recreate your symptoms, try to bring your chin to your chest. Again, some stretch in the back of your leg is normal. You are looking for a recreation of the leg pain you get while you are running.
Figure 2. Straight leg raise
If these tests don’t reproduce your pain and/or you don’t have any back pain, it is likely your sciatic nerve is getting compressed in the pirifomis muscle. This tends to be more common in runners than a lumbar issue. Try sitting on a tennis or lacrosse ball or try a figure 4 stretch on your back to see if this recreates your symptoms.
Then, you can utilize the slump or straight leg raise positions to help “glide” your sciatic nerve back and forth by pointing and flexing your toe in either the slump or straight leg raise position. Research has shown that nerve sliders in the hamstring muscles are effective in increasing hamstring flexibility in addition to static hamstring stretching. Similarly, another recent study showed that focusing on neural tissue mobility seems to be more effective than just static hamstring stretching alone.
Conclusion
Keep in mind that having pain in the back of your leg while running is not normal! If you have been stretching your hamstrings and calves consistently and haven’t noticed a change, it is very possible that you are experiencing symptoms of neural tension.
Poor running mechanics is also a risk factor for neural tension, so check out In Motion PT’s return to running page for more info.
Stay tuned for In Motion Physical Therapy’s next blog post for more tips! In the meantime, give us a call to schedule your running analysis to improve your running stride and efficiency.
References
- https://www.ncbi.nlm.nih.gov/books/NBK507908/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3267445/ (Figure 1)
- Langford, Trevor. “Neural tension: don’t let it hamper your free range of movement!” https://www.peakendurancesport.com/
- https://www.ncbi.nlm.nih.gov/books/NBK539717/ (Figure 2)
- https://www.sciencedirect.com/science/article/abs/pii/S1466853X15000140
- https://www.sciencedirect.com/science/article/abs/pii/S1746068913000941