CPT6 Chapter Review chapter 2 PDF

Preview

Summary

cpt training info for nasm, anatomy physiology...

Description

NASM Essentials of Personal Fitness Training (6th ed.)

CHAPTER REVIEW Chapter 2 – Basic Exercise Science Overview Learning about the basic anatomical structure of the human body is critical to understanding how movement is created and how the body will respond to various types of training. The body is made up of three major components that must work together to create movement; the nervous, skeletal, and muscular systems. Together, they make up the Human Movement System, also known as the kinetic chain. If all three systems are not optimally working together, movement becomes dysfunctional and can lead to injury. By learning the basic anatomy and physiology of these three systems, you will be able to better understand and apply the various concepts of exercise science.

Chapter Highlights Anatomy of the Nervous System The nervous system is a specialized network of cells (called neurons) that transmits information throughout the body. It senses the internal and external environments, collects and interprets that information, and then sends signals so the body can react accordingly. The more efficiently these signals can be transmitted, processed, and received again, the better the body will function overall. The nervous system is divided into two parts, the central nervous system (CNS) and peripheral nervous system (PNS). The CNS is responsible for collecting and interpreting information, while the PNS senses the environment and tells the body how to respond based on signals from the CNS. Mechanoreceptors Tissues in the body have receptors—known as mechanoreceptors—that sense mechanical information, including touch, pressure, stretching, and motion. When mechanoreceptors sense stimuli, that information is sent to the CNS for processing and interpretation. After processing, nerves transmit information from the CNS back to the muscles to act. Two important mechanoreceptors are muscle spindles and Golgi tendon organs. Muscle spindles sense muscular length, while Golgi tendon organs sense muscular tension. Activation of the Golgi tendon organ will cause the muscle to relax (to avoid excessive tension experienced by the muscle). Activation of the muscle spindle will cause the muscle to contract (to avoid excessive stretching of a muscle). Bones The skeletal system gives shape and form to our bodies. It protects internal organs, produces blood cells, stores minerals, and provides the structure from which muscles create leverage. Knowing the types of bones in our bodies, how they are structured, and where they are located leads to a better understanding of how the entire kinetic chain works to produce movement. Joints Joints are where movement happens, and they are formed by one bone articulating with another. This joint movement is known as arthrokinematics. There are various types of joints within the body that each allow for a

different type of movement to occur. Understanding their structures and functions are essential for learning the various joint motions of which our bodies are capable. Skeletal Muscle Skeletal muscle is the tissue that contracts to generate the forces that produce and stabilize joint motion. It is made up of bundles of individual fibers held together by layers of connective tissue. When a muscle contracts, these individual fibers slide past one another, thus shortening the entire length of the muscle. Skeletal muscle is also subdivided into two types; type I (slow-twitch), and type II (fast-twitch). This allows for some muscles (type I) to be more resistant to fatigue for endurance purposes, while others (type II) contract fast to generate more power. Our muscles are also highly interwoven with the nervous system, which is why they are commonly grouped together as the neuromuscular system . Muscles as Movers Joints are surrounded by muscles on all sides, and the muscles must all work together to create movement. To accomplish this, there are four roles a muscle can play depending on the motion that is required: agonist, synergist, antagonist, and stabilizer. The agonist is the prime mover for a movement. It is the muscle (or muscles) that provide(s) the main source of force generation. For example, the gluteus maximus and quadriceps are agonists during a squat since they generate the primary force for that movement. Other muscles help the prime mover (but are not the main force generator); these are called synergists since they work in synergy with the agonists. For example, during a rowing exercise the biceps brachii and posterior deltoids are synergists because they help the back muscles (latissimus dorsi) perform the movement. In opposition to the agonists on the opposite side of the joint are muscles in the role of antagonist. Antagonists create joint actions opposite to the prime mover. For example, the triceps brachii is an antagonist muscle during a biceps curl. Conversely, the biceps brachii is an antagonist during a triceps pushdown exercise. And finally, instead of generating force, stabilizers support joints during movement. For example, the rotator cuff muscles stabilize the shoulders during a chest press exercise. The Endocrine System The endocrine system is made up of the glands that secrete hormones into the bloodstream and the receptors that interact with those biochemicals. Hormones regulate bodily functions including mood, tissue function and development, and metabolism. The function of the endocrine system can be enhanced by improving physical fitness with integrating training. Key hormones for fitness professionals to understand include: • • •

Insulin and glucagon—secreted by the pancreas; regulate blood glucose for use by all bodily cells for energy production. Catecholamines, such as epinephrine (adrenaline) and norepinephrine—produced by the adrenal glands; responsible for readying our bodies for activity and the fight or flight response. The “sex hormones,” testosterone and estrogen—differentiate the male and female reproductive systems; associated with muscle growth (specifically testosterone, which is more concentrated in men) and the secondary sexual characteristics (e.g., facial hair for men, breast development for women).

• •

Growth hormone—secreted by the pituitary gland; mainly responsible for stimulating growth during puberty. Cortisol—a hormone that is released in times of stress and stimulates tissue breakdown for a ready source of energy to overcome a stressor.

Key Terms Human movement system—The combination and interrelation of the nervous, muscular, and skeletal systems. Nervous system—The communication network within the human body. Sensory function—The ability of the nervous system to sense changes in either the internal or external environment. Integrative function—The ability of the nervous system to analyze and interpret sensory information and produce the appropriate response. Motor function—The neuromuscular response to the sensory information after interpretation. Proprioception—The cumulative sensory input to the central nervous system from all mechanoreceptors that sense body position and movement. Neuron—The functional unit of the nervous system. Sensory (afferent) neurons—Neurons that transmit nerve impulses from effector sites (such as muscles and organs) via receptors to the brain and spinal cord. Interneurons—Neurons that transmit nerve impulses from one neuron to another. Motor (efferent) neurons—Neurons that transmit nerve impulses from the brain and spinal cord to effector sites. Central nervous system—The portion of the nervous system that consists of the brain and spinal cord. Peripheral nervous system—Cranial and spinal nerves that spread throughout the body. Mechanoreceptors—Sensory receptors responsible for sensing distortion in body tissues. Muscle spindles—Mechanoreceptors sensitive to change in length of the muscle and the rate of that change. Golgi tendon organs—Mechanoreceptors sensitive to change in tension of the muscle and the rate of that change. Joint receptors—Mechanoreceptors surrounding a joint that respond to pressure, acceleration, and deceleration of the joint. Skeletal system—The body’s framework; composed of bones and joints. Bones—Structures that provide the resting ground for muscles and protection of vital organs. Joints—Junctions of bones and connective tissues; where muscles cause movement to occur. Axial skeleton—Portion of the skeletal system that consists of the skull, rib cage, and vertebral column. Appendicular skeleton—Portion of the skeletal system that includes the upper and lower extremities. Remodeling—The process of resorption and formation of bone. Osteoclasts—A type of bone cell that removes bone tissue (resorption). Osteoblasts—A type of cell that is responsible for bone formation. Epiphysis—The end of long bones, which is mainly composed of cancellous bone, and house much of the red marrow involved in red blood cell production; one of the primary sites for bone growth. Diaphysis—The shaft portion of a long bone. Epiphyseal plate—The region of long bone connecting the diaphysis to the epiphysis where growth in the length of the diaphysis occurs; the growth plate.

Periosteum—A dense membrane composed of fibrous connective tissue that closely wraps all bone except the articulating surfaces in joints. Medullar cavity—The central cavity of bone shafts where marrow is stored. Articular (hyaline) cartilage—Cartilage that covers the articular surface of bones. Depressions—Flattened or indented portions of bone which can be muscle attachment sites. Processes—Projections protruding from the bone where muscles, tendons, and ligaments can attach. Vertebral column—A series of irregularly shaped bones called vertebrae that houses the spinal cord. Arthrokinematics—Joint motion. Synovial joints—Joints held together by a joint capsule and ligaments and are most associated with movement; produce synovial fluid to lubricate joints. Non-synovial joints—Joints that do not have a joint cavity, capsule, connective tissue, or cartilage. Ligaments—Fibrous tissue that connects bones together and provides stability, input to the nervous system, guidance, and the limitation of improper joint movement. Muscular system—Series of muscles that moves the skeleton. Epimysium—A layer of connective tissue that is underneath the fascia and surrounds the muscle. Perimysium—The connective tissue that surrounds fascicles. Endomysium—The deepest layer of connective tissue that surrounds individual muscle fibers. Tendons—Connective tissues that attach muscle to bone and provide an anchor for muscles to produce force. Sarcomere—The functional unit of muscle that produces muscular contraction and consists of repeating sections of actin (thin) and myosin (thick) filaments. Neural activation—The contraction of a muscle generated by neural stimulation. Motor unit—A motor neuron and all of the muscle fibers it connects to. Neurotransmitters—Chemical messengers that cross the neuromuscular junction (synapse) to transmit electrical impulses from the nerve to the muscle....