Muscles, Bones & Joints - A beginners guide

Discussion in 'Health and Fitness' started by Simon, Oct 8, 2011.

  1. Simon

    Simon Administrator Admin Supporter MAP 2017 Koyo Award

    Here is a beginners resource which sets out to explain some basic structure, joints, muscles and terminology, which otherwise may leave the new starter confused.

    The Muscles

    The human body had 600 muscles, which are used to facilitate movement, posture, production of heat and energy and core stabilisation.

    There are three types of muscle tissue.
    1. Cardiac
    2. Smooth
    3. Skeletal

    Cardiac muscle forms the heart walls, while smooth muscle is found in the walls of internal organs such as the stomach and blood vessels.
    Both of these muscle types are activated involuntarily by the autonomic nervous and hormonal systems.

    Skeletal muscle forms the bulk of the muscles we commonly know.
    Muscles attach to the bones via tendons. The attachement points are known as the origin and insertion, and to work a muscle it need to be contracted between those points.

    contraction_isometric.jpg

    Here you can see the bicep originates toward the shoulder and inserts down toward the elbow.
    The origin is usually the least moveable point, acting as the anchor, while the insertion is usually the most moveable part and can be drawn toward the origin.

    In order to develop a balanced (and safe) exercise programme it is important to understand the origin and insertion points of the muscles, what movement they cause and what joint(s) they cross.

    Diagram_of_Muscular_System.jpg

    The Skeleton

    Our skeleton consists of bones, ligaments (which join bone to bone) and joints.
    The primary role of the skeleton is to support the muscles, protect the soft tissue and internal organs, storage of surplus minerals and the formation of red blood cells in the bone marrow of long bones.

    The word skeleton originates from a Greek word meaning dried up. Children are born with 350 bones, which fuse as they grow, forming single bones.
    Adults have 206 bones.

    The nervous system interacts with the muscles to facilitate the contraction and relaxation of muscles, while the articular system of joints allows the levers of the body to move.

    Anatomical Planes

    The body is divided into three imaginary planes.

    1. Median - Sagittal Plane
    2. Transverse - Horizontal Plane
    3. Coronal - Frontal Plane

    dp_planes-BB.gif

    Why is knowing this necessary?

    Understanding how a joint moves is important in analyzing how an exercise works.

    Here are some examples, in addition to an explanation of movement terms: -

    Movement - Flexion
    Plane - Sagittal
    Description - Decreasing the angle between the two structures
    Example - Standing barbell curl
    (This becomes an extension when doing the downward phase of this movement)

    Movement - Elevation
    Plane - Coronal
    Description - Movement of the scapula
    Example - Shoulder shrugs

    Movement - Abduction
    Plane - Transverse
    Description - Movement of scapula away from the spine
    Example - Seated low cable pully row

    Movement - Circumduction
    Plane - All planes
    Description - Complete circular movements (shoulder or hip)
    Example - Swinging the arms in circles

    Movements usually occur in pairs (as shown in the example of the barbell curl).
    Typical pairs are: -

    1. Flexion and extension
    2. Abduction and adduction
    3. Internal and external rotation
    4. Protraction and retraction

    Glossary of terms

    Abduction - Movement of a limb away from the centre line.
    Adduction - Movement of a limb toward the midline of the body.
    Agonist - A muscle that causes motion.
    Antagonist - A muscle that moves the joint opposite to the movement produced by the agonist.
    Compound exercise - Involving two or more joint movements.
    Concentric - A muscle contraction resulting in it shortening.
    Eccentric - The contraction of a muscle during its lengthening.
    Extension - Straightening, extending or opening a joint, giving an increased angle between the two bones.
    Flexion - Bending a joint, giving a decrease in the angle.
    Isolated - An exercise that involves on joint movement.
    Isometric - Contracting a muscle without significant movement.
    Pronation - Internal rotation of of the foot or forearm.
    ROM - Range of motion.
    Supination - External rotation of the foot or forearm (results in the hand or foot facing upwards).

    Resource: Anatomy for strength and fitness training by Mark Vella.
     
    axelb, Fish Of Doom and SamuraiMaster like this.
  2. dormindo

    dormindo Active Member Supporter

    As a former (and still licensed) massage therapist, I like this.

    paz,

    dormindo
     
  3. Mangosteen

    Mangosteen Hold strong not

    I tried explaining how you should not punch (showed his focused power punching video) saying that there should be no ulnar deviation in his wrist.
    He did not understand.
     
  4. righty

    righty Valued Member

    Mostly good, however some things are not quite correct although sufficient for a basic understanding of the matter.

    For example, the number of bones in an adult can differ slightly between individuals.
     
  5. Simon

    Simon Administrator Admin Supporter MAP 2017 Koyo Award

    Righty, please add where you see fit.

    The idea is this for this to be a beginners guide to understand some of the terminology used here.
    Anything you want to add can only help.
     
  6. dormindo

    dormindo Active Member Supporter

    To be sure, the human being can vary quite a bit in terms of nerve placement, number of bones, etc. but A&P is meant to be the general layout of what would be expected in the general population.

    There might be some things that I might be interested in adding, but it'd definitel y have to be later in the week--enough on my plate as it is. Suffice to say, for now, that info on the nerves, dermatomes, fascial planes, chapman's reflexes and more could be added in.

    paz,

    dormindo

    PS: Job's Body by Deane Juhan and Thomas Myers' Anatomy Trains are good reads.
     
  7. Atre

    Atre Valued Member

    Add to Glossary
    Medial - Towards the centre line of your body eg. Medial side of the knee is inside the leg
    Lateral - Away from the centre line of your body eg. Lateral side of the knee is the outside of the leg
    Anterior - Towards the front of your body
    Posterior - Towards the back of you body
     
  8. Atre

    Atre Valued Member

    Really really like the thread/OP as is, I'd also suggest for a full beginners guide it might be useful to add some basics on joint structure (glossy surfaces and synovial fluid), what kind of things can go wrong and how best to fix 'em
     
  9. Simon

    Simon Administrator Admin Supporter MAP 2017 Koyo Award

    Thanks for the addition Atre.

    Nice idea for either a new thread, or an article and get yourself a publisher tag?
     
  10. righty

    righty Valued Member

    Sorry if that first comment may have come off too critical. I'd just come off marking a pile of science reports. I'm also just annoying like that.

    But anyway a few constructive comments...

    -Further to Atre's comments, also add distal and proximal to the glossary.
    -I think an overview of joints should be added - after all it's in the title and introduction but that's it. Depends of course on how much detail you want to go into, but in my opinion a short summary of the different types of joint would be within the scope of this article.

    At the end of the day this is your article so do what you will. If it was in a wiki form I might change a few others things but as I said, it's your creation.

    EDIT: Ohh, I thought this was an article not a general post. Are you going to add it as an article? I hope so.
     
    Last edited: Oct 12, 2011
  11. Simon

    Simon Administrator Admin Supporter MAP 2017 Koyo Award

    No problem righty, Please add some information on joints and don't see this as just my article.

    Anything that adds knowledge is all good in my book.
     
  12. Late for dinner

    Late for dinner Valued Member

    I'm not sure how I ended up on this page or how I missed it before but I thought that it might be good to add a few ideas. I will try to put up a couple in the next while that I hope are useful.

    First there is the concept of function versus action. A muscle might straighten the knee while sitting eg the quadriceps but the hamstrings might be more involved in straightening the knee when squatting/deadlifting because the foot cannot be lifted when one is weight bearing so the knee is pulled back instead. This can be very confusing as sometimes a muscle will have the action of doing one thing (concentric straightening of the knee for the quads) but the function will be different (the function of the quads can be to eccentrically control flexion of the knee).

    So sometimes you need to be careful that you don't get confused that the action of the muscle may have little to do with it's function. :' )

    LFD
     
    Last edited: May 8, 2017
  13. VoidKarateka

    VoidKarateka Valued Member

    Nice post, thanks for sharing! May be a good idea to get a couple images of the skeletal system as well?
     
  14. SamuraiMaster

    SamuraiMaster New Member

    wow, very comprehensive, better than other articles on the subject.
     
    Simon likes this.
  15. Simon

    Simon Administrator Admin Supporter MAP 2017 Koyo Award

    Thank you.
     

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