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Certificate III in Fitness - Module 4 Health Science and Nutrition
CONTENTS CONTENTS ........................................................................................................................................................................ 1 ADDITIONAL RESOURCES ................................................................................................................................................. 2 OVERVIEW ........................................................................................................................................................................ 3 PART A ‐ APPLY ANATOMY AND PHYSIOLOGY PRINCIPLES IN FITNESS............................................................................ 3 ANATOMICAL TERMINOLOGY ....................................................................................................................................................5 STRUCTURAL LEVELS OF THE HUMAN BODY ...........................................................................................................................9
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THE SKELETAL SYSTEM ..............................................................................................................................................................11 BONE DEVELOPMENT ................................................................................................................................................................17 THE MUSCULAR SYSTEM ...........................................................................................................................................................22
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THE CARDIORESPIRATORY SYSTEM .........................................................................................................................................34 THE NERVOUS SYSTEM..............................................................................................................................................................43 THE LYMPHATIC SYSTEM ..........................................................................................................................................................48 THE ENDOCRINE SYSTEM ..........................................................................................................................................................50 ENERGY SYSTEMS .......................................................................................................................................................................55 THE DIGESTIVE SYSTEM.............................................................................................................................................................60 PART B ‐ PROVIDE HEALTHY EATING INFORMATION TO CLIENTS.................................................................................. 62
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OVERVIEW OF HEALTHY EATING .............................................................................................................................................62
DIETARY TRENDS ........................................................................................................................................................................70 SIGNS OF GOOD AND BAD NUTRITION ...................................................................................................................................72 NUTRIENTS ..................................................................................................................................................................................65 CHRONIC DISEASE & NUTRITION .............................................................................................................................................73 DIET AND BODY COMPOSITION ...............................................................................................................................................80 NUTRITIONAL REQUIREMENTS AND INTENSE EXERCISING .................................................................................................81 BODY IMAGE ISSUES ..................................................................................................................................................................81 PROVIDE DIETARY RECOMMENDATIONS ............................................................................................................................... 84
CERTIFICATE III MODULE 4 ASSIGNMENT ...................................................................................................................... 87
© Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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ADDITIONAL RESOURCES ADDITIONAL READING Further Readings: Eating Drinking Before Sport
Proteins
Eating and drinking during and after sport
Vitamin and Mineral Supplements
Carbohydrates and the glycemic index
Dietary Guidelines Australia abridged
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Fats and Oils
WEBSITES
betterhealth.vic.gov.au
Inner Body
innerbody.com/htm/body.html
anatomyandphysiologyi.com/
Anatomy & Physiology
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Better Health Channel Victoria
WEB PAGES & SEARCHES Search ‘Anatomy quiz’ Search ‘Anatomy pictures’
Search ‘Muscular system of the body’
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Search ‘How does the cardiovascular system work’
Search ‘How does the body produce energy’
Search ‘What happens the [insert body system] during exercise’ Search ‘Dietary guidelines Australia’
ACTIVITIES
Throughout this module and the following modules we have created activities for you to complete which will help your learning and understanding of the topics within each module. These activities are not compulsory or marked, however we recommend they are completed to help understand topics within this module.
ACTIVITY
Complete the following……
PLEASE NOTE: Handouts can be found at the back of the module following page 81.
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OVERVIEW This module covers the basic anatomy and physiology related to fitness, as well as looking at providing clients with healthy eating information. The anatomy and physiology section initially looks at basic terminology and components of fitness before breaking down each individual system within the body and applying it to the fitness setting.
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The health eating section identifies the difference between good and bad nutrition, which may be linked to fad diets, as well as examining chronic diseases that may exist within the body that may result from poor nutrition.
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PART A ‐ APPLY ANATOMY AND PHYSIOLOGY PRINCIPLES IN FITNESS WHAT IS ANATOMY AND PHYSIOLOGY?
ANATOMY is the study of internal and external structure of the body.
PHYSIOLOGY is the study of how living organisms perform the various functions of life.
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As a fitness instructor you need to understand how the relevant anatomical and physiological concepts apply to the development of a fitness program. Or in other words, you need to first know how the body works before planning an effective fitness program.
WHAT IS EXERCISE PHYSIOLOGY?
Exercise physiology is the study of the function of the human body during exercise conditions. As a fitness instructor understanding how the body reacts, changes and modifies as a result of the body undergoing exercise is key to planning and marinating successful fitness programs for your client.
COMPONENTS OF FITNESS RECAP
The components of fitness allow us to be in a state of health, which is a state of complete mental, physical and social well‐being. There are five main components to fitness:
Body Composition
Cardiovascular Endurance
Muscular Strength
Muscular Endurance
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Flexibility
BODY COMPOSITION Body composition is used to describe the percentages of fat, bone and muscle in the human body. Body composition is affected by factors such as diet and exercise. Muscular tissue takes up less space in our body than fat tissue. Our body composition, as well as our weight, determines lean mass.
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CARDIOVASCULAR ENDURANCE Cardiovascular endurance is the ability of the heart to deliver blood to working muscles and then their ability to use it (e.g. running long distances).
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Frequent and regular aerobic exercise has been shown to help prevent or treat serious and life‐ threatening chronic conditions such as high blood pressure, obesity, heart disease, Type 2 diabetes, insomnia, and depression. Endurance exercise before meals lowers blood glucose more than the same exercise after meals. According to the World Health Organisation, lack of physical activity contributes to approximately 17% of heart disease and diabetes, 12% of falls in the elderly, and 10% in breast cancer and colon cancer. Aerobic exercise also works to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training).
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MUSCULAR STRENGTH
Muscular strength is the limit to which muscles can exert force by contracting against resistance (e.g. holding or restraining an object or person).
Strength refers to the ability of muscles to generate force against physical objects and/or resistance. In the fitness world, this typically refers to things like how much weight you can lift or how many push ups you can do. This type of resistance can include dumbbells, barbells, resistance bands, machines, cables or your own body. When lifting heavy weight, you increase strength, muscle size and connective tissues such as ligaments and tendons. The muscular system is made up of muscles, tendons, ligaments and connective tissue (fascia) that help to support internal organs. All of these systems work together to provide the body with stability and posture, motion, heat, circulation and help in digestion.
MUSCULAR ENDURANCE
Muscular Endurance is the ability of a muscle or group of muscles to sustain repeated contractions against a resistance for an extended period of time (e.g. rowing or cycling). It helps to increase bone mineral density, improve tolerance to lactic acid concentrations, and strengthen the integrity of muscular connective tissue.
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FLEXIBILITY Flexibility is the ability to achieve an extended range of motion without being impeded by excess tissue, like fat or muscle (e.g. executing a leg split).
ANATOMICAL TERMINOLOGY
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Flexibility refers to the range of motion or movement of a joint or group of joints. The common factor affecting flexibility is the inability of the muscles and tendons surrounding a joint to stretch to an optimal length. Lack of mobility causes stiff joints and pain resulting in poor posture. Flexibility lengthens the muscle and tendon tissue surrounding joints and increases the range of motion. It also assists in preventing injuries, enhances biomechanical efficiency, coordination between muscles groups and relieves joint pain and postural issues.
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To best describe the manner in which the body moves and also the positions the body can be in naturally, we use standard terms to create uniformity in the ranges of movement.
ANATOMICAL POSITION
This is used to describe the reference point from which the body moves from. The body stands in the erect position, arms by the sides with palms facing anterior, feet parallel so that the toes and head face forwards.
PRONE AND SUPINE POSITIONS
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Lying face down is called prone position. Lying face up is called supine position.
PLANES OF BODY MOTION
The body is divided into many planes of motion to describe movement.
The SAGITTAL plane passes through the body from anterior (front) to posterior (back) and divides the body into left and right parts. The movement that exists in this plane is flexion and extension. I.e. hip flexion
The FRONTAL (coronal) plane passes through the body from lateral to medial (ear to ear) and divides the body into anterior and posterior parts. The movement that exists within this plane is adduction and abduction. I.e. hip abduction.
The TRANSVERSE plane passes through the body level with the horizon and divides the body into superior (upper) and inferior (lower) parts. The movement that exists within this plane is rotation, i.e. humeral internal rotation.
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ACTIVITY
List 3 types of exercise or movement that a relevant to each plane of motion:
Sagittal
Frontal
Transverse
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DIRECTIONAL TERMINOLOGY
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towards the head
Inferior
towards the feet
Anterior
towards the front of the body
Posterior
towards the back of the body
Medial
towards the mid‐line of the body
Lateral
away from the mid‐line of the body
Proximal
towards the attachment point of a limb
Distal
away from the attachment of a limb
External/superficial
more towards the surface of the body
Internal/deep
more towards the inside of the body
Peripheral
away from the centre of an anatomical system
Central
towards the centre of an anatomical system
Unilateral
on one side of the body only
Bilateral
on both sides of the body
Contralateral
on the opposite side of the body
Palmar
on the same side as the palm of the hand
Plantar
on the same surface as the sole of the foot
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Superior
Dorsum
on either the back of the hand or back (top) of the foot
MOVEMENT TERMINOLOGY Flexion
bending a joint (reducing the angle at a joint)
Extension
the act of straightening (increasing the angle of a joint)
Abduction
movement away from the midline of the body
Adduction
movement towards the midline of body
Circumduction
the circular movement of a limb
Inversion
turning inward of a limb
Eversion
turning outward of a limb
Horizontal flexion
moving forward in the horizontal plane
Horizontal extension returning to original position Hyperextension
refers to the over extension, or moving beyond the normal extension range
Pronation
internal rotation of the forearm/hand so the palm is facing downwards or backwards; and a similar movement with the foot where the foot/ankle rolls inwards.
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Supination
external rotation of the forearm/hand so the palm is facing upwards or forwards; and a similar movement of the foot where the foot/ankle rolls outwards
Plantar flexion
the action of extending the foot downwards so the plantar (sole) of the foot faces posterior.
Dorsi flexion
the action of flexing the foot downwards so the dorsal (top of the foot) of the foot faces posterior.
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List the movement occurring in the following movements: ACTIVITY
(tip – use the name of the joint along with the movement i.e. shoulder flexion)
(up phase)
Press‐up
(down phase)
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Kicking a ball
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Bicep Curl
Sitting down in a chair
STRUCTURAL LEVELS OF THE HUMAN BODY The body is a complex structure which is made up of many different levels, these are described here:
1. CHEMICAL LEVEL
At this level atoms and molecules combine to make organelles, which determine cell function. These functions can include cell membranes, mitochondria and ribosomes.
2. CELLULAR LEVEL
Life begins with one cell. This cell is replicated through a process called mitosis, until the body get a full set of 46 chromosomes. By adulthood, the body has 10 trillion cells. The other major function on the cellular level is cellular differentiation, which facilitates the specific functions of cells and genes in the human body. Cellular differentiation determines differences in, for example, skin, eye and hair colour. © Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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3. TISSUE LEVEL There are four distinct types of tissue which are produced when like cells come together: o Connective tissue which includes bone, blood, and cartilage o Muscular tissue which gives the body definition, produces force and causes motion o Epithelial tissue which is the skin that covers the body o Neural tissue which transmits electrical pulses throughout the body.
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4. ORGAN LEVEL Organs are formed when like tissue comes together and most organs contain all four tissue types. There are 76 organs in the human body, each performing a specific function such as: o blood movement (the heart)
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o waste management (the liver and kidneys) o respiration (the lungs)
o regulation of body temperature (the skin)
o glucose maintenance (kidneys and pancreas)
5. SYSTEM LEVEL
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All previously mentioned levels come together to form systems that perform specific human functions. These organ systems include the cardiovascular system (blood flow), the gastrointestinal system (body waste) and the skeletal system (human bones). In all, the human body has 11 organ systems.
6. ORGANISM LEVEL
This is the final level, where all the previous levels function together and form an organism.
(Sourced from: http://anatomyandphysiologyi.com/)
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THE SKELETAL SYSTEM
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ANTERIOR SKELETAL SYSTEM
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ANTERIOR SKELETAL SYSTEM
SPINAL POSTURE © Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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Curvatures of the Spine
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Spinal Movement
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The following diagram indicates the different curvatures of the spine in relation to the 4 sections which consist of the cervical, thoracic, lumbar and sacral spine.
The next diagram shows the degrees of movement possible by the cervical spine, the include; lateral flexion (tilting the head from side to side), flexion and extension (bring the chin closer to the chin and then further away from the chin, and lateral rotation (looking left or right whilst keeping the body facing forward).
The diagram to the right indicates the movement permitted at the thoracic and lumbar spine, this include; lateral flexion (side bending), Flexion and extension (bending forward and back from the hips) and rotation (look left and right moving from the lower part of trunk)
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POSTURAL DEIVATION OF THE SKELETAL SYSTEM Kyphosis This postural deviation involves the increased kyphotic curve of the thoracic spine creating a hunchback or slouching posture. The thoracic spine has a naturally rounded curve; however, in this condition the rounding is exaggerated. The following table indicates the areas that are likely to need addressing and exercises that can improve the condition: Muscles that are likely to be weak and stretched include:
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latissimus dorsi
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abdominals
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pectorialis minor
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gluteals
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pectorialis major
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intercostals
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internal oblique
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anterior deltoid
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Seated rows
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Supermans
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Abdominal stretch
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Resistitive scapula retraction
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Reverse fly
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Back extensions
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Lordosis
Exercises to help this condition include:
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Muscles that are likely to be shortened and tight include:
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Lordosis is a condition where lumbar spine has an over exaggerated lordotic curve (inward curve). A healthy spine possesses a small degree of a lordotic curvature; however, similar to kyphotic the curvature goes beyond the naturally healthy level. The following table indicates the areas that are likely to need addressing and exercises that can improve the condition: Muscles that are likely to be shortened and tight include:
Muscles that are likely to be weak and stretched include:
Exercises to help this condition include:
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Iliopsoas
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Iliopsoas
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Bridge
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Rectus femoris
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Rectus femoris
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Hip flexor stretch
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Lower back erector spinae
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Lower back erector spinae
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Abdominal crunch
Scoliosis
Scoliosis is a postural deviation where they spine is unnaturally curved laterally. The diagram on the right indicates the lateral curvature of the spine. This condition is usually accompanied with vertebral rotation causing the ribs to rotate.
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FUNCTION OF THE SKELETAL SYSTEM Differently shaped bones that join together in a collection form the shape of the human body. When two bones meet they make a joint. The soft tissues of the body are supported by the skeleton for maintenance of form and posture. Vital organs are also protected by the strong structure of the skeleton. Bones store important minerals like calcium, for muscle contractions and transmission of nervous system messages and phosphorus, used for normal cell functionality. Therefore the specific functions of the skeletal system include:
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o Protection – acts as a protective structure for vital organs. Some examples include the skull protecting the brain and the lungs being protected by the rib cage. o Support – the skeletal system provides the framework of the body’s shape, without it the body would not be kept upright.
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o Movement – individual bones within the skeletal system connect together to form joints. There are several different types of joints which allow limited movement planes (explained later). Movement occurs from the muscles which are attached to each bone within the joint. o Blood production – skeletal bones consist of cancellous bone (spongy bone) that contains redbone marrow the blood cell production component. o Mineral storage – the bone can also store minerals within its structure. Calcium us stored within bone matrix and iron can be stored within the bone marrow.
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There are 206 bones in the body connected by a variety of joints. Muscles produce force that causes movement to occur at the joints. The skeleton is further divided into the axial skeleton and appendicular skeleton.
The axial skeleton consists of the: o skull and facial bone
o sternum o ribs
o vertebral column
The appendicular skeleton consists of:
o The pectoral girdle and the arm‐scapula, clavicle, humerus, radius, ulna, carpals, metacarpals and phalanges o The pelvic girdle and the legs – the ilium, o ischium, pubis, femur, patella, tibia, fibula, tarsals, metatarsals and phalanges
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BONES Structure of long bone Articular Cartilage: This is a layer of tough tissue located at the end of the bone. It acts to provide a smooth and lubricated surface for articulation between two bones at a joint.
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Periosteum: This is a thick membrane which covers the outer layer of a bone, apart from the end of long bones.
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Compact bone: one of the main components of bone, it makes up one of two types of bone tissue. Its role is to create and provide a strong structure within the bone.
Cancellous bone: also known as spongy bone, this is the second type of tissue which constitutes bone tissue. It is a weaker, less dense structure that contains red bone marrow for blood production to occur.
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Bony epiphyseal line: In children and adolescents, this line is called an epiphyseal plate and is made of hyaline cartilage. Referred to as the growing plate, it is location where growth takes place within the bone. In adulthood, when growing stops, this hyaline cartilage (plate) turns into an epiphyseal plate.
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THE CARDIORESPIRATORY SYSTEM OVERVIEW OF THE CARDIORESPIRATORY SYSTEM
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The cardiorespiratory system is a combination of the cardiovascular system and the respiratory system working together. The cardiorespiratory system is made up of the heart, blood vessels (cardio elements), two lungs and airways (respiratory elements). The heart and lungs work together to provide the body with adequate levels of oxygen to enable survival.
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This system and all its components work together to transport gases to and from the lungs and cells within the body.
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This system functions together as a whole, but each component has individual roles to play. It begins with the respiratory system inhaling of gases (mostly important gas being oxygen) from the surrounding environment into the lungs. To reach the lungs air travels down the trachea (windpipe) before the trachea branches off into a left and right bronchus (stiff cartilage and smooth muscle make up the trachea and bronchi). To ensure the air is clean mucus is secreted in these airways to filter dust and particles in the air. The air continues to travel through these smaller airways in the lungs called bronchioles and finally into the alveoli (air sacs) of the lungs. The alveoli are surrounded by tiny blood vessels known as capillaries. Once in the lungs gaseous exchange occurs, which is where oxygen that has reached the alveoli is transported through the alveolar walls into the blood vessels. At the same time carbon dioxide is exchanged in the opposite direction moving from the blood vessels to the alveoli. The carbon dioxide is simply forced out the body during exhalation of the lungs.
The next stage is the transportation of the oxygen within the blood which is called gaseous transport and is now the responsibility of the cardiovascular system. The blood travels back to the heart from the lungs where it is pumped out to the rest of the body.
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THE PROCESS OF TRANSPORTING AND EXCHANGING OXYGEN AND CARBON DIOXIDE In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction. The respiratory system works with the circulatory system to carry gases to and from the tissues. In air‐breathing vertebrates like ourselves, respiration of oxygen includes four stages: Ventilation – moving of the ambient air into and out of the alveoli of the lungs.
Pulmonary gas exchange – exchange of gases between the alveoli and the pulmonary capillaries.
Gas transport – movement of gases within the pulmonary capillaries through the circulation to the peripheral capillaries in the organs, and then a movement of gases back to the lungs along the same circulatory route.
Peripheral gas exchange – exchange of gases between the tissue capillaries and the tissues or organs, impacting the cells composing these and mitochondria within the cells.
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Respiratory and cardiovascular activities are intensified during exercise. However, respiratory activity is highly voluntary (you can control your breathing) compared to cardiovascular activity which is totally involuntary.
MAIN MUSCLES IN RESPIRATION
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During respiration, there are several muscles which have the ability to assist with respiration. These can be broken down into main muscles that are used during normal breathing and accessory muscles which are additional muscles that are active during elevated breathing, mainly during exercise. Some of the main muscles are also mainly function during inspiration or expirations and this will be indicated in the description of the muscle.
Main muscles used during respiration:
Diaphragm: the main muscle used in respiration controlling the volume of the lungs, it is located at the base of the lungs. It contracts to flatten and increases the volume within the thoracic region to draw air into the lungs (inhalation). It then relaxes and bulges upwards to push air out the lungs (exhalation). Internal and external intercostal muscles: located inbetween the ribs, these muscles act as a synergist to the diaphragm contracting and relaxing to increase and decrease the lung space, assisting inhalation and exhalation. Scalenes: the scalenes have a small role during normal breathing, which is to help stabilise the first and second ribs.
Accessory muscles used during respiration: Sternocleidomastoid and Scalenes: helping elevate the ribs during forced respiration, this aids inspiration. © Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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Rectus abdominals and External Obliques: these muscles help respiration in two different ways; firstly they help depress the ribs during expiration, forcing air out more rapidly; and secondly they compress the internal organs which they lie above, helping push the diaphragm upwards.
STRUCTURE OF HEART The heart is made up of three layers: o Pericardium – thin protective outer layer.
o Endocardium – thin inner lining of the muscle.
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o Myocardium – thick muscular wall.
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The heart is split up into 4 chambers, the two top chambers are called the atrium (left and right) and the two bottom chambers are called the ventricles (left and right). The atrium chambers receive blood into the heart and the ventricles chambers pump blood away from the (Illustration sourced from http://www.heartfoundation.org.au/) heart. There are two main blood vessels which are attached to the heart, which are:
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o Aorta – is the main artery which exits the heart and is pumped out by the left ventricle o Vena Cava – is the main vein which returns the blood back to the heart and enters into the right atrium
Within the heart there are several valves which help prevent the backflow of blood into chambers, these include: tricuspid valve and mitral valve.
CARDIAC CYCLE
Stage 1 – The blood enters the right atrium of the heart via the vena cava veins. Stage 2 – Once in the right atrium, the blood is pumped into the right ventricular Stage 3 – From the right ventricle, the blood is pumped through the pulmonary arteries to the lungs. Stage 4 – The blood then re‐enters the heart from the lungs into the left atrium.
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Stage 5 – The blood is then pumped into the left ventricle where it is pumped out through the aorta to the rest of the body.
BLOOD PRESSURE Blood pressure is the pressure the blood exerts on the artery walls and is considered during two different stages of the cardiac cycle – systolic and diastolic. Systolic measures the pressure exerted on the artery walls whilst the blood is being pumped out of the heart to the rest of the body.
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Diastolic measures the pressure exerted on the artery walls whilst the blood is resting (or not being pumped out to the rest of the body).
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When blood pressure is taken, it will produce two readings giving the above measurements. The diastolic is the lower number as there will be less pressure exerted when the heart is resting. How blood pressure is controlled
Blood pressure is usually measured using a sphygmomanometer and is measure in mmHg.
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An individual’s blood pressure can change quite often throughout the day as a result of daily stimulants. The body changes blood pressure using receptors that are within the smooth muscular wall of the arterioles. These receptors detect how relaxed or constricted the vessels are. Any narrowing will restrict flow causing less blood to be transported through the vessels and around the body. This is then relayed onto the brain, which stimulates a nervous and hormonal reaction, inducing the heart to beat faster and overcome the restriction. As a result this causes high blood pressure, and can occur for short periods of time; however, if it is prolonged then hypertension is developed. Normal blood pressure is considered to be 120/80. Effects of exercise on blood pressure
The effect of exercise on blood pressure can be related to short‐term affects or long‐term effects, they consist of the following:
Short‐term effects – during exercise the body requires additional oxygen and nutrients, so to achieve this, the cardiovascular and the respiratory systems work harder. The heart, a component of the cardiovascular system, is required to pumper harder and faster to push more blood around the body. As a result, the pressure exerted on the artery walls increases during the contraction phase but remains constant during the relaxation of the heart. Therefore systolic blood pressure increases and diastolic blood pressure remains relatively constant. Long‐term effect – the long term effects of exercise include the decrease in blood pressure at rest. This is achieved as a result of the heart and cardiovascular system being more efficient when the body is not exercising. To achieve this long term effect, exercise is must be performed on a regular basis, over a long period of time.
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SYSTEMIC AND PULMONARY CIRCULATION The following illustration shows the circulation system and the route it takes. Systemic circulation is the circulation from the heart to the whole body, whereas pulmonary circulation is the name given to the circulation of blood passed the lungs.
STRUCTURE AND FUNCTION OF BLOOD VESSELS
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Within the cardiovascular system, there are several different types of blood vessels which have different structures. These include:
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Arteries – these are blood vessels which transport blood away from the heart (with the exception of the pulmonary artery which transports blood from the lungs to the heart). The blood transported by arteries are always oxygenated.
Veins – These are blood vessels that transport blood towards the heart (with the exception of the pulmonary vein which transports blood from the heart to the lungs). Veins always carry deoxygenated blood. Capilaries – these are blood vessels which attach arteries and veins and are responsible for allowing gases to diffuse in and out to and from other cells.
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THE CARDIORESPIRATORY SYSTEM AND EXERCISE The cardiovascular system serves five important functions during exercise: o Delivers oxygen to working muscles o Oxygenates blood by returning it to the lungs o Transports heat (a by‐product of activity) from the core to the skin o Delivers nutrients and fuel to active tissues o Transports hormones
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Exercise places an increased demand on the cardiovascular system. Oxygen demand by the muscles
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increases sharply. Metabolic processes speed up and more waste is created. Also AN increased amount of heat is produced from the increased metabolism; therefore the whole body temperature will rise. To perform as efficiently as possible the cardiovascular system must regulate these changes and meet the body’s increasing demands.
HEART RATE
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Your heart rate is an important guide for your exercise program because it can tell you how exercise is affecting you. Your heart rate can be used to measure intensity of exercise as well as gains in fitness. Knowing what to expect and how to gauge your heart rate can make your exercise program more effective.
MAXIMAL HEART RATE
Maximal heart rate is the greatest heart rate that can be measured when individuals are exercising to the point of stopping because they cannot exercise longer. Several equations have been developed to estimate maximal heart rate: Maximal heart rate = 220 minus age (low estimate) Maximal heart rate = 210 minus [0.5 x age] (high estimate) Maximal heart rate = 226 minus age (estimate for older individuals)
Maximal heart rate can, however, vary greatly among different individuals of the same age.
SUBMAXIMAL HEART RATE
Submaximal heart rate is where the heart is beating below the maximal heart rate. A submaximal heart rate is a rate at which an individual can sustain for a period of time, whereas a maximal heart rate would be too high to sustain. Aerobic Exercise Aerobic exercise is any sustainable activity that causes a rise in the heart rate. This activity must be done for at least three minutes at a higher than resting intensity. As the intensity of aerobic © Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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exercise increases, so does your heart rate. When maximum capacity of work is achieved your heart rate will plateau. Aerobic exercise can be performed in various modes. Exercises which involve upright positions like jogging will result in an increased heart rate compared to those done in a seated or reclined position like bike riding or swimming. Resistance Training
RATING OF PERCEIVED EXERTION (RPE)
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Resistance training done with or without movement causes an increase in heart rate. However, this increase is different from aerobic exercise. An increase in heart rate from resistance training is due to an increased after‐load in the heart, whereas during aerobic exercise it is due to an increased volume of blood being moved throughout the body.
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Also explained in module 2, the RPE is most commonly used in cardiovascular training but can just as easily be applied to strength training. It is a subjective rating that the person exercising assigns to the intensity of their exercise based on their perception of how hard the physical exertion was.
When you ask a client how hard they are training on a scale of one to ten, you are asking for their RPE.
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If the client answers that they are at a 10 (they are probably lying because at 10 you can’t talk!) it would equate to lifting to failure, or collapsing at the end of a run from exhaustion. It means they have exhausted all the energy or strength that they have. An RPE of between 1 ‐ 5 would be consistent with a warm up or cool down.
OXYGEN DEMANDS FOR FITNESS ACTIVITIES Aerobic exercise includes lower intensity activities performed for longer periods of time. Activities such as walking, running, circuits, cycling and swimming require a great deal of oxygen to generate the energy needed for prolonged exercise (i.e. aerobic energy expenditure). However, in sports which require repeated short bursts of exercise, it is the anaerobic system that enables muscles to recover for the next burst. This includes sports such as weightlifting and sprinting. Training for many sports demands that both energy producing systems be developed.
SHORT TERM PHYSIOLOGICAL CHANGES OF THE CARDIORESPIRATORY SYSTEM WITH EXERCISE When an individual participates in an exercise program or any physical activity, there are short term changes which occur to the cardiorespiratory system. These include: o Increased capillary dilation
o Blood shunting to working muscles o Increased temperature within the working muscles o Development of micro‐tears to the muscles © Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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PHYSIOLOGICAL ADAPTATIONS OF THE CARDIORESPIRATORY SYSTEM Following a cardiovascular endurance focused exercise program, there are some adaptations which occur to cardiovascular system. These include: o Heart size – the muscular walls of the heart hypertrophy (especially the left ventricle). This makes the heart a more powerful pump, enabling it to push more blood around the body. o Increase volume of blood vessels around the muscles and alveoli in the lungs. o Blood pressure – as explained earlier, the blood pressure decreases following a long period of exercise.
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o Volume of blood pumped out the heart changes:
o Stroke volume (SV) – this is the amount of blood that leaves the heart in one pump. As a result of the being a more powerful muscle the SV increases
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o Decrease resting heart rate – as a result of the heart becoming more efficient, it does not have to pump as often to deliver the same amount of blood. This is a result of more blood being pumped in one pump. o Venous return becomes more efficient, so blood returns to the heart through the veins easier. o The red blood cells increase their capacity to pick up and transport oxygen and carbon dioxide. Therefore circulating blood has oxygen extracted more effectively.
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o Lung capacity increases – the ability or the lungs to expand and inhale oxygen increases. This can be a result of increased muscles involved in breathing. o Improve respiratory muscles – the diaphragm and intercostal muscles hypertrophy and increase their capacity to perform (reducing their fatigue level) o Increase number of alveoli in the lungs for gases exchange.
ACTIVITY
Explain what blood pooling is and how it can be avoided:
Blood pooling definition
How to avoid blood pooling
© Australian College of Sport & Fitness Certificate III ‐Module 4 ‐ Course Notes ‐ 1405B
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