Chapter 4 – The Human Movement System in Fitness
- Human Movement System:(Kinetic Chain) is composed of three related systems: Nervous(central and peripheral nerves), Muscular (muscles, tendons, ligaments and fascia), and Skeletal (joints) systems.
- Nervous System: the system of nerves and nerve centers in an animal or human, including the brain, spinal cord, nerves, and ganglia.
- Sensory Function: The human body’s ability to recognize changes in the environment within the body or outside of the body.
- Integrative Function: the nervous system processes and interprets the sensory input and makes decisions about what should be done in each moment.
- Motor Function: The human body’s ability to respond to the information received from the sensory nervous system.
- Proprioception: the total nervous system input to the central nervous system creating the awareness of the position of one’s body
- Neuron: a specialized, impulse-conducting cell that is the functional unit of the nervous system, consisting of the cell body and its processes, the axon and dendrites
- Sensory (afferent) neurons: a nerve cell that conducts impulses from a sense organ to the central nervous system
- Interneurons: a nerve cell that transmits nerve impulses between neurons.
- Motor (efferent) neurons: a nerve cell that conducts impulses to a muscle, gland, or other effector
- Central Nervous System: the part of the nervous system comprising the brain and spinal cord.
- Peripheral NervousSystem: the portion of the nervous system lying outside the brain and spinal cord that includes the cranial and spinal nerves
- Mechanoreceptors: any of the sense organs that respond to vibration, stretching, pressure, or other mechanical stimuli.
- Muscle Spindles: a proprioceptor that conveys information on the state of muscle stretch or length, important in the reflex mechanism that maintains body posture.
- Golgi Tendon Organs: A proprioceptive sensory nerve ending embedded among the fibers of a tendon that is sensitive to muscle tension.
- Joint Receptors: sensory receptors in joint capsules that contribute (along with other sensory inputs) to awareness of joint position and movement (proprioceptive sensation).
- Skeletal System: The framework of the body, consisting of bones and other connective tissues, which protects and supports the body tissues and internal organs.
- Bones: the hard connective tissue forming the substance of the skeleton, composed of a collagen-rich organic matrix impregnated with calcium, phosphate, and other minerals.
- Joints: the movable or fixed place or part where two bones or elements of a skeleton join.
- Axial Skeleton: the skeleton of the head and trunk including the skull, vertebral column and rib cage.
- Appendicular Skeleton: The bones of the limbs, including the bones of the pelvic girdles.
- Remodeling: mature bone tissue is removed from the skeleton (a process called bone resorption) and new bone tissue is formed (a process called ossificationor new bone formation).
- Osteoclasts: cells that take away or remove mature bone tissue.
- Osteoblasts: cells that are responsible for building up new bone tissue.
- Epiphysis: a part of a bone separated from the main body of the bone by a layer of cartilage and subsequently uniting with the bone through further ossification.
- Diaphysis: the long, narrow portion of a bone
- Epiphyseal Plate: the disk of cartilage between the shaft and the epiphysis of a long bone during its growth.
- Periosteum: the normal investment of bone, consisting of a dense, fibrous outer layer, to which muscles attach, and a more delicate, inner layer capable of forming bone.
- Medullary Cavity: the small cavity in the shaft of a long bone where blood cell formation occurs and marrow is stored.
- Articular (hyaline) cartilage: a firm, elastic, flexible type of connective tissue that covers the end of a bone that makes up a joint.
- Depressions: a flat area of the bone
- Processes: a point in the bone used for muscular or ligamentous attachment
- Vertebral Column: the column of 24 bones making up the spinal column. (7 cervical, 12 thoracic, 5 lumbar)
- Arthrokinematics: Description of the movement of the joint surfaces when a bone moves through a range of motion.
- Synovial Joints: joins bones with a fibrous joint capsule that is continuous with the periosteum of the joined bones.
- Non Synovial Joints: non-movable joint that excludes the joint capsule, cartilage and ligaments.
- Ligaments: connects bone to bone and provides joint support.
- Muscular System: All the muscles of the body collectively, especially the voluntary skeletal muscles.
- Epimysium: the outermost layer of muscular connective tissue that encompasses the muscle body.
- Perimysium: the middle layer of muscular connective tissue that encompasses the muscle fascicle.
- Endomysium: the deepest layer of muscular connective tissue that encompasses the muscle fiber.
- Tendons: a cord or band of dense, tough, inelastic, white, fibrous tissue, serving to connect a muscle with a bone.
- Sarcomere: like the nueron is to the nervous system the sarcomere is the functional unit of muscle or any of the segments of myofibril in striated muscle fibers; composed of actin and myosin.
- Neural Activation: the nervous system activation of a muscle fiber via the neuromuscular junction.
- Motor Unit: a motor neuron and the muscle fibers innervated by its axon.
- Neurotransmitters: any of several chemical substances, as epinephrine or acetylcholine, that transmit nerve impulses across a synapse to a post-synaptic element, as another nerve, muscle, or gland.
(Compare the above with definitions from the text)
This image from (SEER Training Modules, n.d.) is similar to the one you may find in the book. It shows how the bundles of muscle fibers can be broken down further as you explore more into the skeletal muscle.
Acetlycholine initiating the muscular contraction.
Excitation-contraction coupling is the process of the nervous system stimulating a muscle to contract. This is known as the sliding filament theory. In this figure xenical where to buy shown in the book it gives 10 steps in the initiation and end of the contraction. Below the steps are more condensed to assist in understanding. Check out Fitness Mentors Study Guide for the NASM CPT Exam to learn what you need to know specifically about this chart.
- The Neurotransmitter ACh is released and attaches to receptors generating an action potential down the T tubules.
- Action potential triggers Calcium (Ca2+) release
- calcium binds to troponin removing the blocking action of tropomysosin and exposing the actin active binding site.
- Contraction occurs by the myosin cross bridges alternately attach to actin and detach, pulling the filaments closer to the center of the sarcomere. Detachment of actin from myosin requires ATP.
- Removal of Calcium by active transport into the sarcoplasmic reticulum after the action potential ceases.
- Tropomyosin restores its location, covering the actin active site so no more contraction occurs.
Compare to Table 4.1
Type I: Endurance fibers; small; more oxygen and mitochondrial density; less power.
Type II: Less enduring; less oxygen delivery; more power and force, larger than type I.
Compare to Table 4.2
Muscle as Movers
Muscle functions are categorize as an agonist, synergist, stabilizer or antagonist.
- Agonist muscles: prime mover
- Synergist muscles: assist the same movement as the prime mover
- Stabilizer muscles: Stabilize the joints of the body during the movement
- Antagonist muscles: relax to allow the prime mover to work efficiently
|Dumbell Curl||Bicep||Brachioradialis||Rotator cuff||Tricep|
|Calf Raise||Gastrocnemius||Posterior tibialis||Intrinsic Muscles of the ankle, knee and hip||Anterior tibialis|
Compare to Figure 4.27 – Atria and Ventricles
Atria and Ventricles
The heart has two pairs chambers called the Right atrium and ventricles. The functions of the chambers are as follows:
The atriums are located on either side of the heart. Right Atrium is designed to receive the blood that is coming to the heart from the whole body and the Left Atrium is designed to receive the blood that is coming to the heart from the lungs.
The ventricles are also located on either side of the heart. Right Ventricle have thin walls because of a low pump of blood that flows to the lungs which is a short distance from the heart. The Left Ventricle has much thicker walls because of a high pressure pump of blood that flows to the rest of the body.
Compare to Table 4.4 – Functions of Blood
The cardiovascular system.
This slide above is provide from a presentation from share slide (stewart_j, n.d.). It is similar to the table that is shown in the book. NASM deems it important to understand the functions and support mechanisms of blood.
Table 4.30 – The Respiratory Pump – The abdominal and thoracic structures that contribute to the expansion and contraction of the lungs.
Muscles of the respiratory pump consist of:
Inhalation: Diaphram, Scalenes, Pec Minor and Sternocleidomastoid.
Exhalation: Abdominals and Internal intercostals.
How the respiratory pump works: