This part of the ANS controls the “fight or flight” responses. It can produce body reactions such as increasing blood flow to the skeletal muscles as much as 1200%! Whoa. I would think zhan zhuang is more about calming the sympathetic and the parasympathetic nervous system (controls “rest and digest”). However these systems are not binary and mutually exclusive. They work at the same time, apparently in opposition yet in complementary fashion. They are seen as a sort of gas pedal and brake that can have phases in between. Is it possible that one can train these systems to partially use the fight or flight response, under some control, rather than out of control – sort of balancing the bodily states between the two extremes in a more optimal way? The systems are always on but become more active for different situations. The sympathetic nervous system is active for actions requiring quick responses. I would think one would want the maximum level of calmness as much as possible while being able to tap into the sympathetic nervous system and somewhat control the gas pedal to any extent possible to make use of it without going overboard. Some quotes from the wikipedia entry on the fight or flight response:

  • It is relatively rare that a threat from another animal results immediately in fight or flight. Usually there is a period of heightened awareness … An example of this is kittens playing: each kitten shows the signs of sympathetic arousal, but they are aware of each other’s intent not to inflict real damage.
  • Although the emergency measure of the stress response is undoubtedly both vital and valuable, it can also be disruptive and damaging. In most modern situations, humans rarely encounter emergencies that require physical effort, yet our biology still provides for them. Thus we may find our stress response activated in situations where physical action is inappropriate. This activation takes a toll on both our bodies and our minds.
  • Prolonged stress responses may result in chronic suppression of the immune system, leaving the sufferer vulnerable to infection by bacteria and viruses.
  • Repeated stress responses can be caused not only by real threats, but also by mental disorders such as post-traumatic stress disorder, in which the individual shows a stress response when remembering a past trauma

Overuse of the stress response seems to be a uniquely modern problem. I can hear George Costanza’s father shouting “Serenity Now!!!”. From those points above and various readings on qigong, zhan zhuang, meditation, and so on, I am guessing we would like to be able to hit the gas pedal slightly at will but then regulate it so that it’s not going off all the time (e.g., road rage) — getting the “Zen calm” homeostasis as the normal state so that use of the sympathetic nervous system is kept to a bare minimum yet very “ready” to activate. I think that’s also why the yiquan folks say to not do the “maximum” activation of “almost movement”, imagining the maximum resistance, in shi li very often. Past a certain point or frequency, it’s harmful for that relaxed homeostasis and harmful for the immune system.

That last point in the above wikipedia excerpts suggests just having a memory can trigger the sympathetic nervous system to overload, an example of how powerful the mind/body connection is. Since we can somewhat control, especially via meditation or biofeedback training, not having (letting go of) thoughts that will produce this undesired response, it seems we can gain some conscious (but indirect?) control over the body’s nervous system responses. I guess that qigong, zhan zhuang, yoga, meditation, and biofeedback are all training the nervous system in this way, but the mechanism is not fully understood. As a practical matter, no one really needs to understand the mechanism, though. “Just do it”. I am getting the newfangled Wii Fit soon. If only it had some kind of biofeedback device to go with it… old tech + high tech would be super cool.