As a newbie, I’m usually too worn out, sweaty and befuddled to notice, except when the instructor barks out (about once per class), “your other left john – turn the other way!”
Does it really matter? I mean we’re going to do both sides anyway – right? or was it left? ugh!
I don’t know, but came across an interesting science article today entitled, “Forebrain emotional asymmetry: a neuroanatomical basis?” [doi:10.1016/j.tics.2005.10.005] by Bud Craig from the Barrow Neurological Institute in Phoenix, AZ.
Dr. Craig reviews ample evidence showing how the nervous system in the BODY (peripheral nervous system) is very different on the LEFT vs. the RIGHT sides …
The peripheral nerves of the autonomic nervous system are the only major nerves of the body that are asymmetric.
and that these bodily asymmetries lead to asymmetries in the brain …
The confluence of these strikingly parallel asymmetries suggests a homeostatic neuroanatomical model of emotional asymmetry, in which the left forebrain is associated predominantly with parasympathetic activity, and thus with nourishment, safety, positive affect, approach (appetitive) behavior, and group-oriented (affiliative) emotions, while the right forebrain is associated predominantly with sympathetic activity, and thus with arousal, danger, negative affect, withdrawal (aversive) behavior, and individual-oriented (survival) emotions.
This model instantiates neurobiologically the psychological proposal that a hypothetical ‘calm and connection system’ opposes the arousal/stress system.
In a nutshell, information sent up to the left brain stem – mainly via the vagus (a.k.a – the living Kundalini serpent in your body) – makes you feel really calm and connected. Yoga, with its myriad forms of breathing, twisting, inverting etc. seems to have perfected the art of engaging the vagus “Kundalini” nerve and generating maximum amounts of parasympathetic nervous system activity. This is a gooood thing indeed!
So, if the LEFT side of the brain stem and brain receive information that make you feel calm and connected, why the RIGHT FOOT? … because, in our cerebral cortex, the the left half of the brain controls the right side (foot included!) of the body.
Does anyone really know for sure? Perhaps I’d do best not to worry about why, and just focus on feelin’ good during practice.