The vegetative systems are those body systems that support the living process, that neither require nor greatly benefit from conscious attention. Though this could be considered a gift, our culture has deep distrust for any function not under immediate willful control of the ego. Also, changes take place in the vegetative systems, especially with the parasympathetic part of the autonomic nervous system, over several minutes or even hours, and certainly not instantly For these two reasons our culture at large ignores the vegetative systems, preferring the so called voluntary nervous system to achieve all ends as quickly as possible.
The term vegetative system was formerly used to designate solely the autonomic nervous system. In this discussion, it can be useful to think of other vegetative systems, the neuro-endocrine system, the vestibular system, involuntary functions of the skeletal muscle system, and the the immune system.
As Wilhelm Reich and Alexander Lowen showed, however, volitionally-dominated actions are mechanical and unpleasureable. They often have a "flung" quality. They lack grace. All satisfying actions , and the large majority of effective actions, are the product of the conscious choice and the vegetative systems working in concert.
It is sometimes said, too simplistically, that the vegetative systems exert involuntary control only. Actually, they can be deliberately influenced, by breathing, imagery, feeling, letting go, certain types of movements or positions, the presence of other people, sex, warming and cooling, massage, meditation, shocking news, what is done with the mouth, stimulating reflexes (including gag reflex), etc ...
All the above practices, strangely, are considered 'alternative' in our culture. Aerobic exercise, along with general health benefits, does have some vegetative effects, and it is endorsed by our culture, perhaps because it is associated with power, endurance, and superiority, which are ego, not body qualities. The pleasureable endorphin effect, though probably not harmful, is actually a dissociative effect, where the mind is in less touch with what is happening in the body. All movement therapies discussed in this website avoid aerobic or cardiovascular stress because 1) it generally works to increase contraction and muscle shortening, and 2) for traumatized people at least, it decreases ventral shift and increases sympathetic shift, and 3) using up oxygen rapidly creates a minor survival stress in the body-one is simply trying to finish-- which makes it hard to change old muscular habits
Vegetative functions can be influenced by drugs of course, but not to their long term betterment, so that will not be discussed here.