• Skip to main content
  • My Training Programs
  • Articles and Tutorials
    • The Fitness Index
    • Nutrition Index
    • Inspirational Index
    • Science Index
  • About Antranik
    • About Antranik
    • Online Coaching
  • Members Area
    • Login
    • Account
    • Quick and Effective Strength
    • Smart Core
    • Work From Home Fitness
    • Hypertrophy
    • Rings Routine
    • Easy Hamstrings
    • Hip Flexibility
    • Shoulders & Upper Back

Antranik.org

Strength & Flexibility Expert

Like! Follow! Subscribe!

  • Facebook
  • Instagram
  • YouTube

The Autonomic Nervous System

Up until now we’ve covered everything in this organizational chart below except for the ANS and visceral sensory system, which are highlighted in yellow.

The autonomic nervous system (ANS) is a system of motor neurons that innervate smooth muscle, cardiac muscle and glands.

The autonomic nervous system has two divisions: Sympathetic and Parasympathetic.  They mostly innervate the same structures but cause opposite effects.  The sympathetic division mobilizes the body during extreme situations such as exercise, excitement and emergencies. Colloquially known as “fight or flight.”  The parasympathetic division controls routine maintenance functions such as to conserve body energy and is colloquially called as “rest and digest.”

To make sense of the picture above, note the following…

A neuron found in the parasympathetic nervous system has:
LONG myelinated axon –> ganglion –> SHORT unmyelinated axon.

A neuron found in the sympathetic nervous system has:
SHORT myelinated axon –> ganglion –> LONG unmyelinated axon.

Now is a good time to make sure we differentiate that the ganglion we are talking about is not the same as the dorsal root ganglia.  The “ganglia” in the ANS are motor ganglia made up of cell bodies of motor neurons.  The “dorsal root ganglia” is in the sensory somatic part of the peripheral nervous system and are sensory ganglia made up of cell bodies of sensory neurons.  Review the location of the dorsal root ganglia here: CNS: Spinal Cord

click for the larger view if you can’t see this well

The Parasympathetic Division

The sacral outflow comes from spinal nerves S2 – S4 and innervates:
2nd half of large intestine (smooth muscle)
Urinary bladder and ureters (smooth muscle)
Reproductive organs/erectile tissues of external genitalia (smooth muscle)
This is what points the penis.
The cranial outflow is made up of CN and this is what they innervate:
III (Oculomotor) – constriction of pupils.  The pupil is really just a hole; the absence of light.  The iris itself has a smooth muscle inside of it.  These muscles are circular.  There’s other smooth muscle fibers that run like spoke wheels that dilate the pupils.
VII (Facial) – lacrimal gland (tears), nasal mucus glands, salivary glands
IX (Glossopharyngeal) – parotid gland (which is a salivary gland)
X (Vagus) – heart (cardiac muscle), lungs (bronchi smooth muscle), liver/gallbladder (glands), stomach (smooth muscle and secretions), pancreas (gland), small intestine and 1st half of large intestine (smooth muscle and secretions)

The Sympathetic Division (T1 – L2)

Note it does the opposite of parasympathetic :
Pupil dilation
Inhibit tear, nasal mucus, saliva production
Skin blood vessel constriction (shunt blood away from skin and to vital organs)
Sweat
Increase heartrate and bloodflow to heart muscle
Bronchodilation
Liver/gallbladder – release glucose
Inhibit rest of digestive system
Inhibit defecation and urination
Ejaculation (shoots, point and shoot, get it?)

Adrenal Medulla

The adrenal medulla is GIGANTIC.  It’s the largest sympathetic ganglia.  The cells are made of modified neurons that have short axons and no nerve processes.  The adrenal cortex is an endocrine organ and the outer layer is the adrenal cortex while the inner layer is the medulla.  When stimulated by preganglionic sympathetic fibers from T8-L1, they secrete large quantities of the excitatory hormones norepinephrine and epinephrine (adrenaline) into nearby capillaries.  When these two hormones are released in the blood they amplify all of this fight or flight stuff to give you more energy.

Use this Table of Contents to go to the next article

Painting by Michael Reedy
The Basics. Start here. This is your Foundation.
  • Intro to human anatomy
  • The building blocks of cells

Epithelial and Connective Tissue

  • Basics of Epithelial Tissue
  • Eight types of Epithelial Tissue
  • Detailed Features of Epithelia
  • Connective Tissue Basics
  • Three Types of Membrane

Skin, Hair, Nails, Sweat Glands

  • Integumentary System Part 1
  • Integumentary System Part 2

The Skeletal System

  • Cartilage and Bones
  • Geography of the Skull
  • Special parts of the skull
  • The Vertebral Column
  • Thoracic Cage, Ribs, Fontanelles

The Muscular System

  • Muscles of the Head
  • Muscles of the Neck and Vertebral Column
  • Muscles of the thorax for breathing and the pelvic floor (The Diaphragm)
  • Muscles of the Abdominal Wall
  • Muscles of the Forearm

The Central Nervous System

  • Fundamentals of the Nervous System and Nervous Tissue
  • CNS: Intro to Brain and Ventricles, Medulla Oblongata, Pons, Mid-Brain and Cerebellum
  • Central Nervous System: Spinal Cord
  • The Diencephalon
  • The Cerebral Hemispheres
  • Functional Areas of The Cerebral Cortex
  • Cerebral White Matter and Gray Matter and Basal Ganglia
  • The Limbic System and the Reticular Formation
  • Protection for the Brain: Meninges, CSF, Blood-Brain Barrier
  • Disorders of the Central Nervous System

The Peripheral Nervous System

  • Peripheral Nervous System: Cranial Nerves
  • Peripheral Nervous System: Spinal Nerves and Plexuses
  • Innervation of the skin: Dermatomes

YOU ARE HERE AT THE ANS

The Autonomic Nervous System

  • The Autonomic Nervous System (Includes sympathetic and parasymphathetic systems)
  • Visceral Sensory Neurons and Referred Pain

Special Senses

  • Chemical Sense: Taste (Gustation)
  • Chemical Sense: Smell (Olfaction)
  • The Eye and Vision

The Cardiovascular System

  • Intro to the Heart
  • Blood Flow of the Heart (Circulation Flow)
  • Myocardium
  • Conducting System of the Heart (Nervous Impulse Flow)
  • The Four Corners of the Heart
  • Layers of the Pericardium, Heart Wall and Spiral Arrangement
  • Function of the Atrioventricular and Semilunar Valves
  • Blood Components, Hemoglobin, Type/Rh Factor, Agglutination
  • Blood Vessels

Specialized Systems

  • The Endocrine System (Pituitary, Thyroid, Pancreas, Adrenal, Gonads, etc)
  • The Lymphatic System (Spleen, Thymus, Lymphatic vessels, nodes etc)
  • The Respiratory System (Lungs, Alveoli, Bronchi, Trachea, Larynx, Nasal cavities, etc)
  • The Immune System
  • The Urinary System: Kidneys
  • The Urinary System: Ureter and Urinary Bladder

Want To Get Strong and Flexible? 💪 Check Out My Programs!

Antranik’s Easy Hamstrings Program

For those who have poor flexibility, tight hamstrings and want a simple program that will help them to get looser in a gentle, non-painful manner. In this … [Read More]

The Ultimate Flexibility Bundle

I have three premium flexibility programs that I offer and many of you have been clamoring for a bundle-package, so here it is! You could now buy the … [Read More]

Antranik’s Hip Flexibility Program

I've created this hip flexibility program for those that would like to improve their flexibility in an efficient manner, with a follow along video that only … [Read More]

Antranik’s Work From Home Fitness Program

In this day and age most people are working from home and struggling to find the balance between stagnation and moving to stay fit. This program was developed … [Read More]

Shoulder & Upper Back Flexibility Program

For anyone who wants better shoulder health, shoulder flexibility, a looser upper back and improved posture, this program takes all the guess work out of it to … [Read More]

Antranik’s Rings Bodyweight Training Routine

This is for anybody who wants to get strong and have fun with a gymnastics-inspired routine. It is highly bodyweight-exercise oriented (no external weights) and … [Read More]

Antranik’s Smart Core Program

I don't know about you but nothing gets me fired up more than working on my abs. It's a unique muscle group that is utilized in every exercise and making it … [Read More]

The Quick and Effective Workout Program

Looking for a simple and straightforward bodyweight-oriented strength training routine that doesn't take too much time? You're not the only one! A survey I … [Read More]

Contact · Login

Get An Exclusive Email Special

when you sign up for our newsletter today

Invalid email address
We promise not to spam you. You can unsubscribe at any time.
Thanks for subscribing! Please check your email for special offer.