Last updated: March 20, 2020

Nerves should slide and glide, but they can tolerate some slight stretching.

This particular concern of Yin Yoga goes something like this

Yin Yoga is bad for the nerves. You should not stretch nerves! Being stretched can easily damage nerves.

 

All forms of yoga can potentially stretch a nerve, not just Yin Yoga, but a stretched nerve is not necessarily dangerous. It could be dangerous, but it could also be therapeutic. It depends on the condition of the nerve, which nerve, where it is, its surrounding environment, the magnitude of the stretch, the duration of the stretch and how much recovery time is allowed after stretching. Healthy nerves love stress—the stress helps to move the nerve, which brings nutrients to it. However, if the nerve is “stuck,” perhaps due to some scar tissue or impingement, then a stress applied to the nerve may result in too much stretch occurring, which may not be great for that nerve. This applies for any kind of yoga!

 

One perspective offered in the journal Physical Therapy suggested that therapists “with an understanding of the adaptive responses of nerves to specific physical stresses will be better prepared to provide reasoned interventions to modify specific aspects of the stresses.”[1] The authors cite research on the effect of both tension (including long-held stretching) and compression of nerves. They write that there are 5 levels of stress that can affect nerves, some for ill and some for good:

 

  • Levels of physical stress lower than the levels required for tissue maintenance (low stress) result in a reduced ability of the tissue to tolerate subsequent stress and are consistent with tissue plasticity and response to functional demand. [So, no stress = no good!]
  • Levels of physical stress in the range required for tissue maintenance (normal stress) result in no tissue adaptations and are considered to maintain a state of equilibrium.
  • Physical stress levels that exceed the range required for tissue maintenance (high stress) result in an increase in the tolerance of the tissue for stress in an effort to meet the mechanical demand.
  • Physical stress levels that exceed the capacity of some components of the tissue (excessive stress) result in tissue injury.
  • Levels of physical stress that are extreme (extreme stress) result in tissue death.

 

It is possible to be at levels 4 or 5, which is too much for the nerves, but this does not mean we want no stress at all, as in level 1. Even a little stress (level 2) may serve to maintain current nerve health. To help the nerves regain optimal health, we need enough stress (level 3) to challenge them! That is where we aim to be in Yin Yoga. The stress is long-held, but moderate. We do not try to hold at the maximum extensions possible

 

In short: Too much stress is not good for our nerves, but too little stress is not good either. A moderate amount of stress can help our nerves move. Healthy nerves glide and slide in the connective tissue beds surrounding them. This movement is normal and healthy for the nerves. Stressing the nerve, whether through an active yoga practice or through Yin Yoga, is good for normal nerves. However, sometimes the nerves get stuck, and when this happens, they no longer slide, but stretch when under tension. Most nerves can tolerate some stretch, but if too much stretching occurs, the nerve fiber can become damaged. In these situations, a yoga practice that places too much stress on that stuck nerve can cause problems. A yoga therapist may be able to work with the student to re-mobilize the nerve and allow it to slide once more.

Return to Topics

[1] K.S. Topp and B.S. Boyd, “From Structure and Biomechanics of peripheral nerves – Nerve Responses to Physical Stress and Implication for Physical Therapists,” Physical Therapy 86.1 (2006).