NASM 2 Basic Exercise Science

Kinetic chain, Nervous, Muscular, Skeletal, Endocrine Systems, connection to exercise

kinetic chain

nervous, skeletal, & muscular systems work together to create movement

3 primary functions of nervous system

sensory, integrative, and motor

Sensory function

ability of the nervous system to sense changes in internal or external environment

Integrative function

ability of the nervous system to analyze and interpret sensory info

Motor function

neuromuscular response to sensory info

Proprioception

body’s ability to sense body position and limb movement- work here improves balance, coordination, and posture enabling the body to adapt to it’s surroundings unconsciously

Neuron

processes and transmits signals electrically and chemically

Parts of Neuron

cell body, axon, dendrites

Afferent neurons

Sensory neurons

Efferent neurons

Motor neurons

Interneurons

transmit nerve impulses from one neuron to another

Effector sites

muscles or glands

Axon

cylindrical projection from cell body that transmits nerve impulses from brain/spinal cord to other neurons or effector sites (muscles, organs)

Dendrites

part of neuron that gathers info from body and send it to brain and spinal cord

Central Nervous System components

brain and spinal cord

Peripheral Nervous System components

cranial and spinal nerves

CNS function

coordinate activity of all parts fo body

PNS function

connect the CNS to the rest of the body and the external environment

Subdivisions of PNS

somatic (voluntary muscles and areas of body) and autonomic* (involuntary areas of body)

Division of Autonomic nervous system of PNS

sympathetic (increase levels of activation in preparation for exercise), parasympathetic (decrease levels of activation during rest and recovery)

Sensory Receptors purpose

convert environmental stimuli into sensory info the brain can use to form a response

4 types of sensory receptors and purpose

Mechanoreceptors (touch and pressure), Nociceptors (pain), Chemoreceptors (chemical interactions smell and taste), Photoreceptors (light)

4 areas you find mechanoreceptors

muscles, tendons, ligaments, joint capsules- include muscle spindles, Golgi tendon organs, and joint receptors

Muscle spindles

sensory receptors within muscles that run parallel to the muscle fibers and are sensitive to change in muscle length and rate of length change- help to regulate contraction of muscles via the stretch reflex mechanism

Golgi tendon organs

specialized sensory receptors located wehre skeletal muscle fibers insert into the tendons of skeletal muscle. They are sensitive to changes in muscular tension and the rate of tension change. When this is activated, the muscle will relax to prevent injury

Joint receptors

located in and around the joint capsule, respond to pressure, acceleration, and deceleration of the joint- they signal extreme joint positions and help prevent injury.

axial skeleton

skull, rib cage, vertebral column

appendicular skeleton

upper and lower extremities

Purpose for bones

leverage and support (posture)

Osteoclasts

remove old bone tissue

Osteoblasts

build new bone tissue

5 Types of bones and example of each

Long (leg), short (carpals), flat (ribs), irregular (vertebrae), sesamoid (where tendon passes over joint- knee)

6 features of a long bone

epiphysis (end of bone), diaphysis (shaft), Epiphyseal plate (growth plate at ends), periosteum (fibrous membrane that coats bone), medullary cavity (holds marrow in center), articular/hyaline cartilage (reduces friction in joints)

arthrokinematics, 3 types

joint motion: roll (femoral condyles in a squat), slide (tibial condyles slide across femoral condyles in knee extension), spin (radius on humerus during pronation/supination of forearm)

6 types of synovial joints and example of each

gliding (carpals), condyloid (finger joints), hinge (elbow), saddle (thumb), pivot (base of skull), ball and socket (hip)

Nonsynovial joints

skull, pubic bones, distal joint between tibia and fibula

Ligaments

bone to bone connection

Tendons

muscle to bone

sarcomere

functional unit of muscle that produces contraction and has repeating sections of actin and myosin between z lines

2 protein structures important to muscle contraction

tropomyosin (on actin- blocks myosin binding sites when muscle is relaxed), troponin (on actin- provides binding sites for calcium and tropomyosin when muscle needs to contract)

neurotransmitter

chemical messenger that crosses the neuromuscular junction (synapse) to transmit electrical impulses from the nerve to the muscle

excitation-contraction coupling

process of nerual stimulation creating a muscle contraction (neural activation leading to sliding filament theory)

Sliding filament theory steps

1. sarcomere shortens as z lines move closer together

2. z lines converge because myosin heads attach to actin filament and asynchonously pull (power strokes) the actin across the myosin resulting in a shorter muscle fiber

2 types of muscle fiber, compare parts, oxygen, size, force, endurance, stabilization, and twitch speed

Type I (slow-twitch)- more capillaries, mitochondria, myoglobin, increased oxygen, smaller, less force produced, slow to fatigue, long-term contractions- stabilization (ex: sitting upright)

Type II (fast-twitch)- less capillaries, mitochondria, myoglobin, decreased oxygen delivery, larger, more force produced, quick to fatigue, short-term contractions- force and power

4 Types of muscles based on function

1. Agonist- prime movers (ex: glutes in hip extension)

2. Synergist- assist prime movers (ex: hamstrings in hip extension)

3. Stabilizer- support/stabilize body (ex: transverse abdominus)

4. Antagonist- opposite action of prime mover (ex: psoas- hip flexor)

Endocrine system

glands that secrete hormones into the bloodstream to regulate a variety of bodily functions (mood, growth/development, tissue function, metabolism, temperature regulation, muscle contraction, protein/fat synthesis, physical and emotional response to stress, etc.)

4 main endocrine glands adn basic functions

1. hypothalamus (much of hormone activity)

2. pituitary (master gland of all other glands, growth, milk, skin pigment, oxytocin, reproductive organs, etc.)

3. thyroid (metabolism, rate of growth)

4. adrenal (corticosteroids and catecholamines- cortisol, adrenaline as stress responses)

Carbohydrate (specifically glucose)

primary energy source during vigorous exercise, principal fuel for the brain

Pancreas produces these 2 hormones for these reasons

1. Insulin- as glucose enters small intestine, elevated levels signal insulin release- it binds with receptors and diffuses into the cell and stores it as glycogen in the liver and muscle

2. Glucagon- released by pancreas when glucose is low- triggers the liver to convert its glycogen stores into glucose and release it into the bloodstream

2 Catecholamines- names, produced by, purpose, explain the process

Epinephrine (adrenaline) and Norepinephrine, produced by adrenal glands (on top of kidneys), prepare body for activity- flight/flight

Process: 1. Workout. 2. Hypothalamus triggers fight/flight 3. Adrenal glands secrete more epinepherine 4. Heart rate increases, blood glucose elevates, blood redistributed to working tissues, airways open 5. Exercise sustained

Testosterone

growth and repair of tissue, secondary male sexual characteristics (hair, muscle mass)

Estrogen

deposits fat to hips, butt, thighs- female secondary sexual characteristics (breast development, menstrual cycle)

Cortisol

catabolic hormone (breaks down tissue)- under stress of exercise it maintains energy supply throughout breakdown of carbs, fats, and proteins- high levels caused by overtraining, excessive stress, poor sleep, and inadequate nutrition can lead to significant muscle breakdown

growth hormone

released from pituitary gland, regulated by hypothalums- stimulated by estrogen, testosterone, deep sleep, and vigorous exercise- increases development of bone, muscle tissue, protein synthesis, increases fat burning, and strengthens immune system

Thyroid hormones

base of neck by adams’s apple- tells thyroid to release hormones- affects carb/protein/fat metabolism, basal metabolic rate, protein synthesis, sensitivity to epinephrine, heart rate, breathing rate, adn body temperature. (Low thyroid function leads to low metabolism, fatigue, depression, cold sensitivity and weight gain)