PSK4U1 (Kinesiology) Notes

Unit 1: Anatomical Terminology

Anatomical Position

  • standing upright

  • head and toes pointed forward

  • hand at your side

  • palms facing forward

Planes

  • Sagittal Plane: moves anteriorly-posteriorly (front to back)

  • Frontal Plane: moves medially-laterally (side to side)

  • Transverse Plane: cuts body into superior and inferior parts (top and bottom)

Axes

  • Anterior-Posterior Axis: front to back of the body

    • perpendicular to the frontal plane

    • ex. cartwheel, jumping jacks

  • Horizontal Axis: left to right of the body

    • perpendicular to the sagittal plane

    • ex. front roll, back roll

  • Longitudinal Axis: top to bottom of the body

    • perpendicular to the transverse plane

    • ex. twist, pirouette

Anatomical Relationships

  • Anterior: in front of

    • ex. the chest is anterior to the spine.

  • Posterior: behind

    • ex. the calf is posterior to the shin

  • Superior: above

    • ex. the nose is superior to the mouth.

  • Inferior: below

    • ex. the knees are inferior to the hips.

  • Medial: towards the midline

    • ex. the bellybutton is medial to the fingers

  • Lateral: away from the midline

    • ex. the ears are lateral to the nose

  • Proximal (limbs): closer to point of attachment

    • ex. the bicep is proximal to the wrist

  • Distal (limbs): away from point of attachment

    • ex. the ankle is distal to the knee

  • Superficial: closer to the surface of the body

    • ex. the skin is the most superficial body part

  • Deep: further from the surface of the body

    • ex. the ribs are deep to the skin

Movement of Joints

  • Flexion: bending joint so angle gets smaller

  • Extension: bending joint to angle gets bigger

  • Abduction: move to the side + away from the body

  • Adduction: move to the side + to the body

  • Supination: rotating your hand so that it is facing forward/anteriorly

  • Pronation: rotating your hand so it is facing backwards/posteriorly

  • Opposition: bringing thumb towards fingers

  • Reposition: returning thumb back to anatomical position

  • Plantar Flexion: pointing toes

  • Dorsiflexion: bringing toes closer to shin

  • Inversion: sole of the foot points medially

  • Eversion: sole of the foot points laterally

  • Internal Rotation: turn body medially

  • External Rotation: turn body laterally

  • Elevation: movement superior/upwards

  • Depression movement inferior/downwards

  • Protraction: movement anterior/forward

  • Retraction: movement posterior/backward

  • Circumduction: combination of abduction, adduction, flexion, and extension (a circle)

Unit 2: Skeletal System

Role of the Skeletal System

  • Structural Support: bones are essentially the frame that everything can attach to - as msucles and tissue are soft they cannot provide structural support

  • Protection: protective cage for more delicate boldy parts

  • Growth Centre of Cells: red blood cells and platelts are made of bones

  • Moineral Reservoir: remove calcium and phosphorous from bones to regulate oricessesz

  • Movement: muscles attach to bones and contrdact to facilitate movement

Type of Bones

  • Long Bones

  • Falt Bones

  • Short Bones

  • Irregular Bones

  • Sesamoid Bones

Axial vs. Appendicular

Axial Skeleton (protection)

  • Vertebral Coloumn: 26 bones

    • 7 cervical vertebrae

    • 12 thoracic vertebrae

    • 5 lumbar vertebrae

    • 1 sacrum + 1 coccyx

  • Rib Cage: 24 bones

    • sternum: consists of 1 bone

    • costal cartilage: connects the ribs to sternum

    • true ribs: have own costal cartilage (1-7)

    • false ribs: share costal cartilage (8-10)

    • floating ribs: no costal cartilage (11-12)

  • Head & Face: 22 bones

    • flat + irrgular bones

    • 8 bones in cranium

    • 14 bones in facial bones

  • Inner Ear: 6 bones

    • stirrup - 3 bones per ear

  • Hyoid: 1 bone

    • anterior to throat

Anatomy of a Long Bone

Types of Fractures

  • Simple: when bone breaks but there is no seperation in the bone

  • Greenstick: when the bone bends but doesn’t break into two pieces

    • happens mostly in children

    • bones aren’t comepletely calcified yet - therefore more flexible

  • Compound: when bone breaks into two parts

    • Displaced: when the two parts of the bone move apart

    • Non-displaced: when the bone breaks into two parts but don’t move apart

    • Comminuted: wehn the bone breaks into multiple pieces

    • Open: when the bone punctures the skin

    • Closed: when the bone does not puncture the skin

  • Joint Fractures: bone breaks inside/around joint (breaking thorugh articular cartilage)

  • Stress Fracture: caused by repetitive pounding + stress on bones

    • when muscles fatigue they lose the baility to absorb the stress put onto them causing it to be transferred to the bone (causing tiny cracks)

    • can be caused by sports, poor footwear, etc.

Aging

  • best defnese for agin is building storng bones during childhood

  • recommended prevention method…

    • balanced diet high in calcium and vitamin D

    • weight-bearing excercise

    • no smoking or excessive alcohol use

    • bone density testing

Bone Cells

  • Osteocytes: mature bone cells located whithin the bone matrix

    • monitors bone matrix and signal communicate with other bone cells to start resorption/formation

  • Osteoblasts: form the bone matrix and responsible for bone growth & repair

    • derived from mesenchymal stem cells and mature into osteocytes

    • purpose: to synthesize the bone matirx

  • Osteoclasts: breaks down bones to form spongy internal structures

Types of Joints

  • Fibrous Joints: bones being attached by connective tissue

    • SYNARTHROSIS: immovable

    • SUTURE: interlocking joints b/w skull

  • Cartilaginous Joints: bones being attached by cartilage

    • AMPHIARTHROSIS: slightly moveable

  • Synovial Joints: bones connected by a joint capsule

    • DIARTHROSIS: most moveable

Types of Synovial Joints

  • Ball & Socket: all planes/axes

    • the “ball” of one joint fits into the “socket” of another

    • ex. hip or shoulder

  • Hinge: sagvittal plane / horiszontal axis

    • CONVEX (rounder) and CONCAVE (indented) portion of bones fit into each other

    • ex. knee, humeroulnar joint

  • Pivot Joint: transverse plane / longitudnal axis

    • round point fits into the groove of naohter

    • ex. ulnoradial joint

  • Gliding Joint: all plane / axes

    • two flat pr slightly curved bone surfaces glide against one another

    • ex. intercarpals, intertarsals

  • Saddle Joint: sagittal & frontal plane / horizontal & anterior-posterior axis

    • flexion-extension & abduction/adduction

    • ex. carpal-metacarpals + sternoclavicular joint

  • Ellipsoid Joint: sagittal & frontal plane / horizontal & anterior-posterior axis

    • ex. metacarpophalangeal joint

Unit 3: Muscular System

Components and Function of MSK System

  • support

  • protection

  • mobility - movemnet of msucles and bones

Types of Muscle Tissue

  • Smooth Muscles: surronds bodies internal organs

    • involuntarily controlled

    • dense + smooth

  • Cardiac Msucle: found only in the heart

    • involunatrily controlled

    • stritated

    • responsible for contracting heart and pumping blood

  • Skeltal Muscles: attach bones msucles to bones via tendons

    • voluntatily controlled

    • striated

Naming of Muscles

  • Location: area or relative position

    • anterior/posterior

    • gluteus

    • radialis

    • tibialis

    • medialis/ laterialis/ intermedius

  • Size: genral or relative size

    • maximus/medius/minimus

    • major/minor

    • longus/brevis

    • vastus

  • Shape

    • trapezius

    • serratus

    • deltoid

    • scalenus

    • rhomboid

    • teres

  • Function/Action

    • flexor

    • extensor

    • abductor

    • adductor

    • rotator

    • supinator

    • pronator

  • Number of Origins

    • BIceps = 2 origins

    • TRIceps = 3 origins

    • QUADriceps = 4 origins

  • Point of Attachemnet

    • ORIGIN: the attachement site - doesn’t move during contraction

    • INSERTION: the attachment site that does not move during contraction

  • Direction of Fibres

    • rectus

    • transversus

    • oblqiue

Agonist and Antagonist

  • muscles are arranged in opposing pairs

  • one muscle does one motion, and another muscle does the opposite action

  • AGONIST: muscle responsible for the movement—the muscle shortening

  • ANTAGONIST: muscle that counteracts the movement—the muscle lengthening

  • STABILIZERS: muscle that controls a joint so that motion can happen at another

Anatomy of Skeletal Muscles

  • muscles are made up of msucle cells - MUSCLE FIBRES

  • muscles are made up of bundles of muscle firbres

  • ENDOMYSIUM: connective tissue surronding the enture muscle

  • FASCICLES: bundles of muscle fibres

    • PERIMYSIUM: connective tissue binds together bundles of fasciculi

    • EPIMYSIUM: stronger connective tissue that binds together bundles of fasciculi

  • epimysium extends and eventually turns int othe tendon

  • this tendon connects to the periosteum of the bond

  • SACROLEMMA: cell membrane of a msucle fibre

  • SACROPLASM: cytoplasm of a muscle fibres

    • contains high levels of calcium, glycogen and mitochondria

  • MYOFIBRILS: long thin filaments of msucle fibre

    • ACTIN FILAMENTS (thin myofibrils) or MYOSIN FILAMENTS (thick myfofirils)

    • these are the functional untis - what is actually getting smaller / contracting

  • ACROMERE: short structures line up end-to-end along the length off the myofibrils

Motor Unit

  • Muscle Twitch: single nerve impulse and the contraction uit causes

  • Motor Neuron: neruon that stimulates a muslce fibre

  • Motor Unit: motor neuron plus the msucle fibres it stimulates

    • SMALL MOTOR UNIT: stimulates a few muscle fibres & produce fine movements

    • LARGE MOTOR UNIT: stimulates a lot of msucle fibres & produces large movements

  • ALL-OR-NONE PRINCIPLE: when an impulse is sent through a motor unit all the msucles fibres in that moto unit will contract to theri fullest potential

    • force of msucle contraction depends on amount of muscle units recruited

Roles of Actin and Myosin

Actin

  • TROPOMYOSIN: actin-binding protein

  • TROPONIN: atached to tropomyosin

    1) as the nerve impulse goes through the msucle fiber it causes a release of calcium ions

    2) the calcium ions cause the tropomyosin to rotate

    3) the tropomyosin rotation exposes the binding site so that the myosin heads can bind

Myosin

  • structure: multiple hinged portions / heads that bind to actin

  • movemnt: myosin heads bend and rotate to pull actin (power stroke)

    • myosin head detaches and reattaches in another spot

  • MYOSIN CROSSBRIDGE: the bondage of the myosin head to the actin filament

Autonomic and Somatic Nervous Systems

Autonomic Nervous System

  • controls involuntary movemnts of cardiac and smooth muscles

  • i.e. sweating, digestion, blood pressure, salivation, hormones

  • these actions are tirggered by AUTONOMIC REFLEXES

Somatic Nervous System

  • combination of central nervous system (CNS) and peripheral nervous system (PNS)

  • controls voluntary senses and movemnts of skeletal muscles

  • i.e. touch, sound, heat, pain, muscle action

  • CENTRAL NERVOUS SYSTEM: made of brain and spinal cord

  • PERIPHERAL NERVOUS SYSTEM: nerves that send information to and from the CNS

    • AFFERENT NERVES: sends info to the CNS

    • EFFERNT NERVES: send info from the CNS

Reflex Arc

  • simple circuit of neurons that allolws the body to respond to stimuli

  • SENSORY NEURON: send information to the CNS

  • MOTOR NEURON: sends information from the CNS

  • INTERNEURON: conencts the sensory and motor neurons in the CNS

    • Step 1: receptor receives stimuli

    • Step 2: sensory/afferent nerve sends impulse to CNS

    • Step 3: interneuron interprets impulse and send out the response

    • Step 4: motor/efferent nerve carriers the response from the CNS

    • Step 5: effector organ carries out the response

Unit 4: Energy System

Energy Nutrients

  • carbohydrates

  • fats

  • protein

Role of Carbohydrates in Energy Supply

  • main soujrce of energy as it is easy to obtain & easy for our bodies to metabolise

  • ver abundant in nature (i.e. starch, sugars, fruits, vegetables)

  • building blockes for cell memebranes

  • provided energy that is easily accesible

  • for of short and long term energy

  • GLUCOSE: simplest carbohydrate

    • stored in skeletal msucles and liver as GLYCOGEN

Adenosine Triphosphate (ATP)

  • made in mitochondria and cytoplasm

  • captures chemical energvy released from food breakdown

  • energy is released when a phosphate is released from the ATP

  • composed of:

    • 3 phosphates

    • 1 adenosine

    • 1 ribose

ATP Synthesization

  • Anaerobic System (w/o oxygen)

    • occurs in cytoplasm muslce cells

    • quick production

    • short-term but high-intensity activities

  • Aerobic System (w/ oxygen)

    • occurs in mitochondria

    • long endurance activities

    • can use glucose, fats and protein

(1) ATP-PC System: first 10-15 seconds of energy

  • ANAEROBIC ALACTIC: does not reuqire oxygen or produce lactic acid

  • occurs in cytosol of msucle cells

  • uses stored ATP and phosphocreatine (PCr)

  • first and quickest pathway to produce ATP

  • provides the hgihest rate of ATP synthesis

  • PHOSPHOCREATINE (PCr) is a compund stored in msucle fibres

    • the phosphate can be broken off the phosphocreatine _ attached to ADP

    • PC + ADP —> ATP + CREATINE

  • this procees is used in the initial stage of exercise + provdes 10-15 seconds of energy

(2) Glycolysis: second 1-3 minutes of energy

  • ANAEROBIC LACTIC: does not require oxygen to produce pyrivate

  • occurs in the cytosol of muslce cells

  • uses glucose (sugar) to make ATP

  • glucose is broken down to make 2 ATP and 2 pyrivate

  • involves 11 complex steps which results in a net gain of 2 ATP

  • PYRUVATE: a molecule made when glucose is broken down by gylcolysis

    • AEROBIC: pyruvate is converted into Acetyl CoA

    • ANAEROBIC: pyruvate is converted into lactic acid

      • pyruvate is converted to LACTATE to replenish the upply of NAD+

      • NAD+ allows for the continued breakdown of glucose

      • LACTIC ACID FERMENTATION

        • NAD+ allows for glucose to for thorugh glycolyiss to produce a net of 2 ATP, 2 pyruvates and 2 NADH

        • 2 NADH allows for pyruvates to go thrujgh fermentation to produce 2 lactates and 2 NAD+ which feeds back into another glucose allowing this cycle to continue

      • LACTIC ACID

        • lactic acid is produced when muscles work for an excessicve amount of time withojut oxygen causing muslce fatigue

        • lactate to react with the H+ ions in the body and produce lactic acid

        • lactic acid build up prevents the breakdown of glucose and decreases the msucles ability to contract

        • it takes aboujt 1-2 hojurs of rest or 30-60 minutes of excercise to recover

(3) Cellular Respiration: third 90+ seconds of energy

  • AEROBIC SYSTEM: requires oxygen

  • occurs in the mitochondria

  • use tbe following cycles:

    • AEROBIC GLYCOLYSIS

      • 2 ATP is produced

      • same pathway as anaerobic lactic system except the pyruvate is converted into acetly coa instead of lactate

      • acetyl CoA enters the KREBS CYCLE

    • KREBS CYCLE

      • 2 ATP is produced

      • produces new compounds that are capable of storing “high energy” electrons - these compounds enter the ELECTRON TRANSPORT CHAIN

    • ELECTRON TRANSPORT CHAIN

      • 32 VATP is produced

      • water and carbon dioxide are the only by-products

  • uses glycogen, fats, and protein to make ATP

  • cellular respiration is the complete breakdown of glucose which produces 36 ATP

Fats and Proteins as an Energy Source

Fats as an Energy Source

  • ideal energy source as it can store more than 2x nergy per gram as carbohydrates and proteins

  • structure: 3 fatty acid chains + 1 glycerol = triglycerides

  • fatty acud needs to be converted into Acetyl CoA but do not go throjugh glycolysis

  • instead, they go through a process called BETA OXIDATION:

    • before enetering beta oxidation, fatty acids need to be broken down into 2 carbon chains whci makes 1 acetyl CoA

    • 16 carbon fatty acids = 8 Acetyl CoA

  • trigylcerides —> fatty acids chain —> 2 carbon chain —> 1 acetyl CoA

Protein as an Energy Source

  • same amount of energy as carbohydrates

  • unlike fats and carbs, proteins are not stored for energy

    • all proteins in the body has a specific function

  • proteins are made up of a combination of 20 amino acids

  • there are essential amino acids - 9 specific amino acids that can be synthesized in the body

    • proteins can be broken down into individual amino acids

    • some amino acids can then be converted into glycogen in the liver

    • protein is used during endurance events or chronic illnesses

    • protein is a backup when other energy stores are unavailable

Muscle Fiber & Myoglobin

  • there is a difference between msucle fibre functionlaity due to its use of oxygen

  • MYOGLOBIN: portein that stores and delivers oxygen in muscle fibres

    • hgih myoglobin levels —> increase ability to use oxygen —> increase aeroobic capacity —> increase ability to sustain excercise

    • thus slow twitch msucle fibres have more myoglobin

3v. Types of Muscle Fibres

  • Type I: slow-oxidative

    • generate energy slowly

    • fatigue-resistant

    • aerobic repiration

    • hgih myoglobin

    • lots of mithcondira

    • red colour

    • narrow diameter

  • Type IIA: fast-oxidative glycolytic

    • intermediate type of muscle fibre

    • allow for hgih-speed energy release

    • can be converted to type I or type IIB

    • medium mygolobin

    • moderate amoung of mitochondria

    • red colour

    • medium diamter

  • Type IIB: fast-glycolytic

    • stores glycogen and hgih levels of enzymes

    • allows for quick conract without the need for oxygen

    • low myoglobin

    • few mitochindria

    • whit colour

    • wide diameter

Tonic vs. Phasic Muscles

Tonic Msucles

  • mostly type I fibres

  • assit in posture and stability during walk, standing, etc

  • lots of little contraction

Phasic Msucles

  • mostly type IIA and type IIB

  • explosive movements

Unit 5: Cardiovascular/Respiratory System

Cardiovascular System

Purpose of Cardiovascular System

  • supply the working cells of the body with oxygen/nutrients and trasnporting waste out of the body

  • control temeperature of the body

  • prevention of infection

The Heart

  • controls and pumps blood through the body

  • MYOCARDIUM: cardiac msucle responsible for contracting and pumping the ehart

  • PERICARDIUM: the protective fluid-filled sac surronding the heart

  • EPICARDIUM: the outermost layer/ tissue of the heart

  • ENDOCARDIUM: the innermost layer/tissue of the heart

Composition of the Heart

  • the heart is compolsed of 4 chambers - 2 atria & 2 ventricles

  • PULOMNARY CIRCULATION: right side

    • controls the de-pxygentaed blood in the body

    • pumps deoxygenated blood to the lungs for expiration of carbon dioxide

  • SYSTEMIC CIRCULATION: left side

    • controls the oxygenated blood in the body

    • pumps oxygenated blood to the owrking cells in the body

Heart Valves

  • precvents blood from flowing backwards throug hthe heart

  • the valves are attached to a special tissues, chordae tendinease, whcih attach to the ventricular wall by papillary msucles

  • these special muscles and tissue prevent the valves from being turned inside out as blood gets pushed against them

Electrical Pathways

  • The myocardium allows for the passage of electronic signals through the body to contact

  • SINOATRIAL NODE (SA NODE)

    • Located in the RIGHT ATRIUM 

    • The pacemaker of the heart

    • Controlled by the autonomic nervous system 

    • Sets the rate at which the heart will beat

  • ATRIO-VENTRICULAR NODE (AV NODE)

    • Located in the junction between the atria and ventricles 

    • Passes the electric signal from the atria to the ventricles 

    • Delays signal so that atria can fully contract

  • The INTERNODAL PATHWAYS cause the message to be sent from the top down

Process of Electrical Pathways Working

  • (1) The SA node generates an electrical impulse

  • (2) These impulses cause the atria to contract pushing blood into the ventricles 

  • (3) The impulse reaches the AV node which delays it slightly 

  • (4) The electrical impulse travels down the BUNDLE OF HIS

    • The bundle of his divides into the right and left bundle branches corresponding to the respective ventricles 

  • (5) Bundle of His fibres spread out into small fibres called PURKINJE FIBRES, which distribute the electrical signal throughout the ventricular muscles

    • Ensure ventricles contract in a coordinated manner; starting from the apex (bottom) moving towards the base (top) of the heart

Blood

  • responsible for carrying oxygen, carbon dioxide and nutrients through the body

  • OXYGENATED BLOOD: blood that has already gone to the lungs and it ready to go to the body

  • DEOXYGENATED BLOOD: blood that has gone to the body and it going back to the lungs to be transported out of the body

Blood Pressure

  • DIASTOLE: where the ventricle fills with blood

  • SYSTOLE: the contraction of the ventricles, where it pumps blood

    • the pressure in the arterial walls during diastole vs. systole

    • reported as sytolic pressure / diatolic pressure

    • average: 120/80 mmHg

Blood Vessels

  • the path way for blood to travel through

  • ARTERIES: carries blood away from the heart

    • main transport of oxygenated blood

    • have thick muscular walls need to pumps and whithstand pressure

    • blood pressure is measured in the arteries

    • ARTERIOLES: small arteries

      • ccontrols the distribition of blood

      • controlled by chemicals released by msucles (nitroc oxide) and nervous system

      • smooth muscles surronding the artiole contract (increase blood flow) or expand (decrease blood flow)

    • CAPILLARIES: even smaller arteries

      • site of gas and nutrient exchange

      • wide enoguh for only one red blood cell to move throguh at a time

      • DIFFUSION: molecules move from high concent to low concent

        • oxygen concent is high in blood and low in muscle fibres

        • carbon dioxide concent is low and high in muscle fibres

  • VEINS

    • carries blood towards the heart

    • Veins come together and form bigger veins as they get closer to the heart 

    • Composed of a thin layer of smooth muscles so that they can contract and expand to allow more blood flow across the body 

    • Have one-way valves that prevent backflow

    • VENULES: small veins

  • CORONARY CIRCULATION: supply the heart cells with blood/energy 

    • Coronary arteries, capillaries and veins that supply the myocardium with blood 

Other Cardiovascular Pumps

  • SKELETAL MUSCLE PUMP: this contraction helps push blood through veins to heart

  • THORACIC PUMP: breathing creates changes in pressure helping blood through abdominal cavity

    • When breath in - diaphragm contracts - increases pressure in abdominal cavity - causes blood in blood vessels to travel to heart

Cardiovascular Dynamics

  • CARDIAC OUTPUT (Q): amount of blood pumped out of the left ventricle in 1 minute

    • UNIT: L/min 

    • At rest typical cardiac output is 5-6 L/min

    • During exercise typical cardiac output is 30 L/min

    • STROKE VOLUME (SV) and HEART RATE (HR) contributes to Cardiac output 

    • CALCULATION: Q = SV x HR | L/min = mL x beats/min 

  • STROKE VOLUME (SV): amount of blood pumped out of the left ventricle per beat

    • UNIT: mL or L

    • LVESV: amount of blood remained in the left ventricle after one beat

    • LVEDV: amount of blood remained in the left ventricle after it is done filling

    • SV might decrease late in exercise due to dehydration 

    • CALCULATION: LVEDV - LVESV

    • 3 FACTORS THAT REGULATE  SV?

      • LVEDV - if there is more blood in the left ventricle, more blood to pump out

      • Strength of contractions - forceful the contracts, amount + force of blood will increase

      • Aortic blood pressure - increases aortic blood pressure = decrease in SV 

        • Left ventricle has to work against the pressure of the aorta 

      • Venous return - if more blood is pooling in the veins then there is less blood that gets to the heart (MOST IMPORTANT FACTOR)

        • 4 FACTORS THAT AFFECT VENOUS RETURN?

          • Vescontriction (less volume of blood in the veins = more in heart)

          • Skeletal muscle pump

          • Thoracic pump

          • Nervous stimulation (increases forces of ventricle contraction)

    • HEART RATE (HR): the number of beats the heart performs per minute

    • UNIT: beats/ min → All Q, SV, and HR increases with exercise

Heart Lab

Temperature Regulation

  • The brain uses blood to transport heat

  • Core temperature increases - causes the bodies chemical reactions to discontinue

    • Transports blood to the skin and extremities where it releases heat into the air via sweating 

    • Veins vasodilate to increase surface area therefore releasing more heat

  • Core temperature drops - the brain redirects more blood to the core instead of the extremities therefore creating cold extremities

    • Veins vasoconstrict therefore less blood pools in the veins on the extremities

Adaptations to Exercise

Short Term Adaptations

  • Increases Cardiac output (Q)

  • Increases stroke volume (SV)

  • Increases heart rate (HR)

  • Redistribution of blood

    • Blood flow increases with exercise towards the working cells + away from organs

    • Veins will vasoconstrict in areas blood is not needed 

Long Term Adaptations

  • Increase in stroke volume (SV) - more blood out per beat
    Increase in the number and size of the capillaries - more O2 can enter muscles 

  • Increases in blood plasma - blood not thick; easier to pump

  • Increases in erythrocytes (rbc) - transports more O2

  • Lowering of one's resting heart rate - if SV increases then HR decreases to make Q equal

Respiratory System

Function of the Respiratory System

  • (1) supply oxygen to the blood

  • (2) remove carbon dioxide from the blood

  • (3) regulate blood pH (acid-base balance)

Internal/External Respiration

  • INTERNAL RESPIRATION: gas exchange at the tissue level - O2 is delivered and CO2 is removed 

  • EXTERNAL RESPIRATION: gas exchange in the lungs, CO2 is leaving the blood and O2 is entering

Conductive Zone

  • upper respiratory tract 

    • All the structures that bring air from the outside environment to the alveoli

    • This includes; mouth, nose, pharynx, trachea, bronchi, and bronchioles

    • PURPOSE OF CONDUCTIVE ZONE:

      • (1) HEAT/COOL air to body temperature (37C)

      • (2) moistens the air

      • (3) filters the air

Respiratory Zone

  • Gas exchange between the air and blood 

  • This includes; respiratory bronchioles, alveolar ducts, alveolar sacs (alveoli), etc

  • ALVEOLI: grape-like structures that provide a large surface area for gas exchange

    • Covered with capillaries

    • Elastic

    • Cell wall is 1 cell thick

  • Respiratory zone has moist surfaces that help gases dissolve and diffusion

Mechanisms of Breathing

  • Diaphragm contracts, which pulls down, causing the chest/rib cage to open up

  • The lungs then can expand and while doing so, air is “suckd” into lungs 

  • When diaphragm relaxes, it pushes upwards, which causes air from lungs to be pushed out of the airway

  • In quiet breathing, alveolar sacs, which are elastic, aid in pushing air out

  • In heavy breathing. The abdominal walls help to forcefully push the air out

Gas Exchange

  • Blood becomes oxygenated / carbon dioxide is removed

  • DIFFUSION: movement of molecules from an area of high concentration to an area of low concentration (follows a concentration gradient)

  • RATE of gas exchange is dependent on PARTIAL PRESSURE which is dependent on BAROMETRIC PRESSURE (which depends on weather and elevation)

  • Concentration of specific gases in respiration is  measured using partial pressure 

    • Partial pressure of each gas may change based on weather & environment 

  • HOW TO CALCULATE PARTIAL PRESSURE?

    • Barometric pressure x % of the gas

Factors Affecting Gas Exchange

  • (1) SIZE OF CONCENTRATION GRADIENT:

    • Concentration gradient increases = diffusion increases

    • HENRYS LAW: amount of gas that will dissolve into liquid is proportional to its partial pressure - diffusion will continue until equilibrium 

  • (2) THICKNESS OF THE BARRIER:

    • Thinner the barrier = faster diffusion 

  • (3) SURFACE AREA:

    • More surface area = more diffusion

    • Anatomy of the lung + alveoli provides a huge surface area 

Oxygen and Carbon Dioxide Transport

OXYGEN TRANSPORT

  • A small amount of oxygen gets absorbed by the plasma (2% of O2)

  • The rest bind to hemoglobin (98% of O2)

  • The amount of oxygen in the blood can vary with environmental conditions 

CARBON DIOXIDE TRANSPORT

  • Must be removed from blood

  • Up to 5-10% is absorbed by plasma

  • 20% binds to hemoglobin

  • 70-75% enter erythrocytes and is transported in the bicarbonate system

Blood pH

  • Blood pH is affected by exercise specifically the release of lactic acid during glycolysis 

  • Amount of carbon dioxide released during exhalation is important in DECREASING the acidity of the blood 

  • Regulation

    • Anaerobic respiration creates lactic acid

    • Lactic acid dissociates into lactate (salt) and hydrogen ions 

    • H+ lowers pH making blood more acidic 

    • Bicarbonate + H+ = carbonic acid

    • Carbonic acid will turn into CO2 and H2O in the lungs lowering pH

    • SOME lactic acid is converted back into glucose by the cori cycle in the liver

Lung Volumes

  • STATIC: volume of the lung determined by genetic structure of the lung

  • DYNAMICS: volume dependent on air flow 

  • TOTAL LUNG CAPACITY: maximum amount of air that the lungs can hold

  • VITAL CAPACITY: maximum amount of air exhaled following maximal inhalation

  • RESIDUAL VOLUME: amount of air left in the lungs after maximal exhalation

Adaptations to Training

  • (1) increase in TIDAL VOLUME (VT)

  • (2) Decrease in FREQUENCY (f)

    •  VE = VT x f

    • These changes happen due to an increase in the strength and endurance of exercise muscles

Oxygen Consumption

  • O2 inspired minus the O2 expired

  • VO2 amount of oxygen used 

  • Proportional to work load 

    • Workload increase = greater VO2 = more O2 used in the body

  • Calculated by measuring the amount of air expired and PO2 if that air 

  • Measured in mL/Kg/min

VO2 MAX

  • Maximum amount of oxygen that one can take in and UTILIZE
    Should occur at maximum SV, HR, and a-VO2 difference 

    • The participant performs incremental exercise to exhaustion

    • Essentially puts the individual in escalating exercise until the end of AEROBIC respiration and into LACTIC ACID threshold until the body shuts down during maximal exercise (ATP-PC and glycolysis)

      • The workload is increased every 1 to 2 minutes

    • Can be found using a cycle ergometer or a treadmill under lab settings where zero air in lost into the environment 

    • Measures AEROBIC fitness

  • VCO2 is measured as well - essentially the measure of the difference between the amount of CO2 expired and CO2 inspired

  • Respiratory exchange ratio (RER) ratio between VCO2 and VO2

    • Tells you what energy system is being used 

  • RER can also be used to tell you what fuel SOURCE us being used

    • LOW RER =  more O2 being consumer than CO2

    • HIGH REP = low O2 bein consumed than CO2

  • RER can increase because of HYPERVENTILATION or buffering of lactic acid 

    • As you breathe faster there is less gas exchange 

  • LIMITING FACTORS:

    • Respiratory system: adequate blood flow + O2 diffusion limitations

    • Cardiovascular system: inadequate blood flow/cardiac output and hemoglobin 

    • Metabolic system” lack of mitochondriaÂ