The Human Body. Australian Institute of Fitness 1 / 42

Transcription

1 The Human Body Australian Institute of Fitness 1 / 42

2 Know Your Body Let s have a look at how the human body is put together. We will look at the different bits that make up the body, how these bits work, and how they work with exercise. Australian Institute of Fitness 2 / 42

3 Organs and Organ Systems The human body is made up of many structures and is incredibly complex, however by breaking it down into smaller bits we can start to see how it is organized. In the body there are different levels of organization: Cells: The smallest structural units; organisation of various chemicals e.g. imagine that you have a handful of different coloured M&M s, each M&M representing a cell Tissues: Organisation of similar cells e.g. now imagine organising the M&M s into groups of different colours, each group representing a type of tissue found in the body Organs: Organisation of different kinds of tissues e.g. imagine that each group of coloured M&M s (tissue) could be layered on top of each, this would represent an organ such as the stomach Organ Systems: Organisation of many different kinds of organs e.g. the stomach, liver, small intestine and large intestine are organs that belong to the digestive system. Below is an image showing the structural organisation of smooth muscle cells making up smooth muscle tissue which makes up the wall of the stomach, an organ, that is part of the digestive system. Australian Institute of Fitness 3 / 42

4 Here are the 11 organ systems of the body. Australian Institute of Fitness 4 / 42

5 Need-to-know Organ Systems Although the body is comprised of 11 organ systems, as fitness professionals we need-to-know more about some more than others. Below are 7 need-to-know organ systems that will be covered in more detail in your course. For now let s get to know the different bits (structures) and how they work together (functions): Australian Institute of Fitness 5 / 42

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7 Get to know your organs and structures with this fun interactive organs game! Australian Institute of Fitness 7 / 42

8 NAVIGATING THE BODY Scientists, doctors, physiotherapists and other healthcare professionals â including fitness professionals â use a common language when referring to body structures and their functions. The language of anatomy has clearly defined meanings that allow us to communicate precisely and prevent confusion. For example, is it correct to say â the wrist is above the fingersâ? This would be true if your arms were by your side, but what if they were above your head? So we need some â rulesâ of the road to help us navigate around the body. Letâ s use the analogy of driving a car and following a map. We know our compass â true north and the bearings from it (south, west and east) â and we use directions to navigate our way from point A to point B. In the body we use a standard position called the anatomical position which is like a compass, and we use terms which we call anatomical directions to relate body parts to one another. Letâ s learn these simple positions and directions that will assist with our body navigation! Australian Institute of Fitness 8 / 42

9 Anatomical Position Descriptions of any region or part of the body relate to a specific stance called the anatomical position. When in the anatomical position the body is standing erect, facing forward, with the head level and the eyes looking straight ahead. The legs are straight, feet parallel and close, flat on the floor and directed forward. The arms are at the sides with the palms facing forward. In the anatomical position the body is upright. When reclining, two other terms are used. If the body is lying face down, it is in the prone position (think prone to pray!). If the body is lying face up, it is in the supine position (think supine, lay on your spine!). Australian Institute of Fitness 9 / 42

10 Planes of Movement When the body is in the anatomical position, it can be divided into three imaginary planes. These planes help us to clarify and specify movements. The sagittal plane divides the body into left and right halves. Think of the midline running down the centre of the body, dividing us into two symmetrical halves. The actions of flexion and extension occur along this plane (forward and backward movement or up and down movement). An example would be lifting and lowering your leg. The leg is moving in the sagittal plane. The frontal plane divides the body into front and back portions. The terms anterior and posterior relate to the frontal plane; the actions of abduction and adduction happen along this plane. An example would be taking your arm out to the side and bringing it back. The arm is moving in the frontal plane. The transverse plane divides the body into upper and lower parts, i.e., it cuts us into top and bottom parts. The terms superior and inferior refer to the transverse plane; rotation happens within this plane. When you twist at your waist, you are rotating in the transverse plane. We often use the term horizontal to replace the term transverse. For example, if your arms are parallel to the floor, you perform horizontal shoulder flexion when you bring your arms together in front of your chest. Australian Institute of Fitness 10 / 42

11 Anatomical Directions and Positions Specific terms are used to help communicate location, direction and position of body structures. These terms replace more general references such as 'above' and 'further away from', which are less precise and can be confusing. Several terms which have opposite meanings are grouped in pairs, such as front (anterior) and back (posterior). Directional and positional terms are used to describe the relationship of one part of the body to another. As such they have relative meanings and make sense only when used to describe the position of one structure relative to another. For example, your knee is above (superior to) your ankle. The terms are as follows: Australian Institute of Fitness 11 / 42

12 SKELETAL SYSTEM Bone tissue accounts for approximately one fifth of the weight of the human body. The major functions of bone tissue and the skeletal system include: 1. Support provides a framework for the body, supports soft tissue, provides a point of attachment for muscle. 2. Protection protects many internal organs from injury such as: the spinal cord (protected by the vertebrae), brain (protected by the skull), reproductive organs (protected by the pelvis), heart and lungs (protected by the ribs and sternum). 3. Movement bones serve as levers to which muscles are attached. When muscles contract, the bones acting as levers produce movement. 4. Storage bones store several minerals which can be distributed to other body parts when needed (e.g., calcium); fat stored in the cells of yellow marrow is an important reserve of chemical energy. 5. Haemopoiesis (blood cell formation) red marrow in certain bones is able to produce blood cells. Australian Institute of Fitness 12 / 42

13 Divisions of the Skeletal System The adult human skeleton consists of 206 bones of various sizes and shapes. This complex structure is divided into two principle divisions: the axial skeleton and the appendicular skeleton. Australian Institute of Fitness 13 / 42

14 The Axial Skeleton The axial skeleton consists of 80 bones and has the function of supporting the main axis of the body whilst protecting vital organs. Bones of the skull, spine and chest are included in the axial skeleton. There are 80 bones of the axial skeleton as follows: Skull = 28 bones Spine = 26 bones Thorax = 25 bones Hyoid = 1 We will look at the major bones in more detail shortly. Australian Institute of Fitness 14 / 42

15 The Appendicular Skeleton The appendicular skeleton contains 126 bones in the upper and lower limbs, and also includes those of the girdles that join the limbs to the axial skeleton (shoulder and pelvic girdles). Bones of the arms, legs, shoulder, pelvis, wrist, ankles, hands and feet are included in the appendicular skeleton. There are 126 bones of the appendicular skeleton as follows: Shoulder girdle = 4 Upper extremities = 60 Pelvic girdle = 2 Lower extremities = 60 We will look at the major bones in more detail shortly. Australian Institute of Fitness 15 / 42

16 NAMING BONES Let s get to know the names of the major bones of the body. Firstly, locate each of the bones on the skeleton. To help you remember the names of the bones, we have provided you with a fun memory tip! Australian Institute of Fitness 16 / 42

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18 Quiz - Naming Bones Ready for a challenge? Open then print the blank diagram of the skeleton. Have a go at labelling as many of the following bones as you can find on the anterior (front) and posterior (back) views of the skeleton: 1. humerus 2. radius 3. ulna 4. scapula 5. clavicle 6. sternum 7. pelvis 8. femur 9. patella 10. tibia 11. fibula. Compare your answers to the labelled skeleton on the previous page. Australian Institute of Fitness 18 / 42

19 ARTICULATIONS Every bone in the body (with the exception of the hyoid) connects to another bone. As the song goes, the hip bone s connected to the thigh bone When bones come together they form articulations, or joints. As we know, bones are rigid levers. By coming together to form joints, which bend in one or more directions, the body is able to move around these joints. Imagine if we did not have joints at the ankle and knee we would be much like a tin man that could not bend the legs. This would make it very difficult to walk around! Australian Institute of Fitness 19 / 42

20 Joint Movement So how do our joints move? Bones come together at joints, allowing our body to move in many directions. Muscle actions are always described as departures from the anatomical position of the body. Some of these joint movements are general and can be applied to several regions of the body, whilst others are quite specific to a single region or even a single joint. These specific movements are also called joint actions. Flexion/Extension The movement at a joint which decreases the angle between two adjacent body segments is known as flexion. The opposite action is known as extension whereby the angle between body segments is increased. In the anatomical position, most joints are extended. When a joint can be extended beyond its normal range of motion it is called hyperextension. Both flexion and extension take place along the sagittal plane. Lateral flexion Lateral flexion occurs only at the axial skeleton, for example, when the head or vertebral column bends to the side. Horizontal Flexion/Extension Horizontal flexion and extension occur at the shoulder and hip joints. When the joint angle decreases as the limb moves in a horizontal plane across the body towards the midline, this is horizontal flexion. Moving the limb away from the midline in a horizontal plane is horizontal extension. Dorsiflexion/Plantar Flexion Plantar flexion and dorsiflexion refer only to movement at the ankle. Plantar flexion is performed by moving the ankle to point the foot into the earth or stepping on a car s accelerator pedal ( plant the foot ). Dorsiflexion is the opposite movement, such as moving the ankle to let off the accelerator. Abduction/Adduction These actions happen along the frontal plane and relate only to the appendages (arms and legs). Movement of a body part away from the midline, either of the body as a whole or that of the hand or foot, is termed abduction. Movement of the body part back toward the midline (i.e., to the anatomical position) is known as adduction. To adduct the fingers or toes is to bring them together; to abduct is to spread them apart. Rotation Rotation pertains only to the axial skeleton, specifically the head and vertebral column. For example, when driving a car or riding a pushbike rotation of the head and neck occurs as you turn your head to check if a car is coming from the adjacent lane behind. These movements Australian Institute of Fitness 20 / 42

21 turn your head to check if a car is coming from the adjacent lane behind. These movements happen along the transverse plane. Lateral/Medial Rotation Medial rotation and lateral rotation occur at the shoulder and hip joints. Medial rotation is when the limb turns in toward the midline (also known as internal rotation). Lateral rotation is the opposite action and swings the limb away from the midline (also known as external rotation). Circumduction This is a combination of the actions of flexion, abduction, extension and adduction, in that order. Together these actions create a cone-shaped movement. This movement is possible only at the shoulder and hip joints. Swimming backstroke involves circumduction at the shoulder joint. Pronation/Supination These are special actions that occur in the forearm and describe the pivoting action of the forearm. Supination ( carrying a bowl of soup ) occurs when the radius and ulna lie parallel to one another. Pronation ( prone to spill it ) takes place when the radius crosses over the ulna, turning the palm down. Protraction/Retraction Protraction and retraction pertain to the scapulae, clavicles, head and jaw. Protraction ( protrude ) occurs when one of these structures moves anteriorly. When a scapula (plural = scapulae) moves forward, creating a hump at the upper back, this is protraction of the scapula. The opposite action would be one of retraction ( retreat ), or movement of the scapula backwards (as in squeezing the shoulder blades together ). Elevation/Depression Elevation and depression refer to movement of the scapulae and jaw. Elevation is movement superiorly and depression is movement inferiorly. The scapulae can be raised to a more superior level, or elevated ( shrugging the shoulders ). The opposite action, depression, involves the pulling down of the scapulae to a more inferior position. Australian Institute of Fitness 21 / 42

22 Upward (Lateral) Rotation/Downward (Medial) Rotation The scapulae are also capable of being rotated upward (laterally) and downward (medially) around a reference point at the tip of the shoulder. The scapulae can be rotated upward around this axis, allowing a full outward swing of the upper limb (shoulder abduction). Or the scapulae can be rotated downward, pushing the inferior angle of the scapulae closer to the midline of the body. Australian Institute of Fitness 22 / 42

23 MUSCULAR SYSTEM There are three different types of muscle tissue: skeletal, cardiac and smooth. Although each type of muscle tissue shares some properties, they differ from one another in their microscopic anatomy, location and how they are controlled by the nervous and endocrine systems. Australian Institute of Fitness 23 / 42

24 Skeletal Muscle Tissue Skeletal muscle tissue is striated and works in a voluntary way. It is less elastic in nature and will fatigue more quickly than other muscle types. It is activated by the central nervous system (CNS) and attaches to and moves the skeleton when it shortens. It is called voluntary muscle tissue because it can be made to contract and relax by conscious control. Australian Institute of Fitness 24 / 42

25 Skeletal Muscle Attachments - Origin and Insertion Muscles attach to bones at points we call attachments, specifically known as the origin and insertion. The attachment referred to as the origin is proximal, that is, the bone which is closer to the trunk, whereas the insertion is distal, away from the trunk. The origin is usually the bone which is stationary when the muscle contracts, whereas the moving bone is usually the site of muscle insertion. When a muscle contracts, the bones to which the muscles are attached are pulled towards each other, thus producing movement at the joint over which the muscle crosses. In fact, there is a direct line of pull from origin to insertion and the muscles work in the direction of the muscle fibre arrangement. During your course, you will learn the muscle attachments of the major muscles. If you want to get a headstart, take a look at the table on the next page. Australian Institute of Fitness 25 / 42

26 NAMING MUSCLES Check out the muscle diagrams below where we have labelled some common skeletal muscles. Throughout your course you will learn these in more detail including the pronunciation - some of the muscles are a mouthful! For now, have a go at locating these muscles on your body. Australian Institute of Fitness 26 / 42

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28 Quiz - Naming Muscles Ready for another challenge? Open and print the blank muscle diagrams. Have a go at labelling the following muscles on the anterior (front) diagram: trapezius deltoid pectoralis major biceps brachii rectus abdominus quadriceps tibialis anterior Then have a go at labelling the following muscles on the posterior (back) view: trapezius (yes, again) triceps brachii latissimus dorsi gluteus maximus hamstrings gastrocnemius soleus Compare your answers to the labelled muscle diagrams on the previous page. Australian Institute of Fitness 28 / 42

29 Quiz - Who Am I? 1. I am a member of the abdominal muscle group. I am a deep muscle that wraps around the trunk much like a corset. I compress (squeeze) the abdomen and feature in core training. 2. I am V shaped and live on the mid back. I attach onto the humerus and pull the humerus down in a movement known as shoulder adduction. I love doing lat pulldowns. 3. I live on the front of the thigh and the number 4 has relevance in my name. I extend the knee in movements such as kicking a ball and squats. Hover your cursorâ over the questions to reveal the answers. Australian Institute of Fitness 29 / 42

30 MUSCLES AND MOVEMENT So how do muscles create movement? Once you know the (a) the region of the muscle (location) and where it attaches and understand that the muscle pulls in the direction of the muscle fibre arrangement (the lines you see on the diagrams), you can work out what it does - joint movement. Once you know what it does, you can work out an exercise that involves that joint movement. There are three tables below to help you put it all together. We have also given you a few tips in the muscle column to help your memory. Go to the followingâ pages to see pictures of common strength exercises thatâ have been referred toâ in the exercise example column. Upper Body Muscle & Tip Deltoid â shoulder pads Pectoralis major â pecs Trapezius - shaped like a kite Latissimus dorsi - V shaped Biceps brachii Triceps brachii Region Where It Attaches Joint Movement Example Exercise Example Shoulder Clavicle & scapula to humerus Chest Neck/ upper back Sternum, clavicle to humerus Cervical & thoracic vertebrae to scapula Mid back Thoracic & lumbar vertebrae, sacrum & pelvis to humerus Front of arm Back of arm Lifts arm up â shoulder abduction Pulls arm to chest â shoulder horizontal flexion Moves scapula â elevation (upper), retraction (mid), depression (lower) Pulls arm down â shoulder adduction Lateral raise Push-up Bench press Wide seated row involves retraction Lat pulldown Scapula to radius Bends elbow â elbow flexion Biceps curl Scapula & humerus to ulna Straightens elbow â elbow extension Tricep dip Trunk Muscle & Tip Rectus abdominus â six-pack External oblique â on the ribs Region Where It Attaches Joint Movement Example Anterior trunk Anterior and lateral trunk Transverse Deep, wraps abdominus â like around the trunk a corset or girdle (not on diagram) Pubis of pelvis to ribs Ribs to pelvis Pelvis and lumbar vertebrae to linea alba (line of connective tissue down the Trunk flexion Trunk rotation Abdominal compression, trunk stabilisation Exercise Example Abdominal curl Oblique curl Hover Australian Institute of Fitness 30 / 42

31 Erector spinae - keeps your spine erect Posterior, deep (not on diagram) centre of the abdomen) Many muscles from pelvis, vertebrae, ribs to skull Trunk/back extension Back extension Lower Body Muscle Region Where It Attaches Hip flexors Front of hip Pelvis & lumbar vertebrae to femur Gluteus maximus Gluteus medius Adductors Hamstrings Quadriceps Buttocks Buttocks Gastrocnemius Calf (posterior) â upper Soleus Calf (posterior) - lower Tibialis anterior Pelvis & sacrum to femur Pelvis to femur Inner thigh/ Pelvis groin to femur Back of thigh Pelvis to tibia & fibula Front Pelvis & ofâ thigh femur to patella & tibia Shin (anterior) Femur to tarsal (heel bone) Tibia & fibula to tarsal (heel bone) Tibia to metatarsals Joint Movement Example Lifts leg up â hip flexion Exercise Example Knee raise Lowers leg â hip extension Deadlift Lifts leg to side â hip abduction and stabilises pelvis Standing cable hip abduction (side leg lift) Lowers leg â hip adduction Standing cable hip adduction Bends knee â knee flexion Deadlift and can extend hip Squat (hamstring assists) Straightens knee â knee extension and can flex hip Lifts heel â plantarflexion Lifts heel â plantarflexion Lifts toes â dorsiflexion Squat Lunge Leg press (machine) Calf raise Calf raise Walking on heels Australian Institute of Fitness 31 / 42

32 Upper Body Strength Exercises Start to familiarise yourself with the following common strength exercises. The first step is to learn what the exercise is called and what muscles they target. The next step is to put the exercise into practice down the gym. It will be an advantage to have experience at these exercises. Lateral raise targets deltiod Shoulder press targets trapezius and deltoid Australian Institute of Fitness 32 / 42

33 Push-up targets pectoralis major and triceps Bench press targets pectoralis major and triceps Wide row targets mid trapezius and deltoid Australian Institute of Fitness 33 / 42

34 Lat pulldown targets latissimus dorsi and biceps Biceps curl targets biceps Australian Institute of Fitness 34 / 42

35 Triceps dip (on bench) targets triceps Australian Institute of Fitness 35 / 42

36 Trunk Exercises Start to familiarise yourself with the following common trunk exercises. The first step is to learn what the exercise is called and what muscles they target. The next step is to put the exercise into practice down the gym. It will be an advantage to have experience at these exercises. Abdominal curl targets rectus abdominus Hover targets all abs especially transverse abdominus Back extension targets erector spinae Australian Institute of Fitness 36 / 42

37 Lower Body Strength Exercises Start to familiarise yourself with the following common strength exercises. The first step is to learn what the exercise is called and what muscles they target. The next step is to put the exercise into practice down the gym. It will be an advantage to have experience at these exercises. Deadlift targets gluteus maximus Squat targets quadriceps, gluteus maximus and gastrocnemius Australian Institute of Fitness 37 / 42

38 Lunge targets quadriceps, gluteus maximus and gastrocnemius Leg press targets quadriceps, gluteus maximus and gastrocnemius Australian Institute of Fitness 38 / 42

39 Calf raise targets gastrocnemius and soleus (calf muscles) Australian Institute of Fitness 39 / 42

40 Common Stretches Static stretching is low force hence low risk and considered the safest and most common form of stretching. It involves lengthening the muscle or muscle group in a slow controlled motion to the point of mild tension but not pain. Technique tips include: Always warm-up the muscles prior to stretching Move slowly into the position and choose positions the client can manage Aim for a sequence of stretches that flow from one to another Make sure you breathe and allow relaxation. Maintain good body alignment, avoid stressing any joints and don t bounce. Hold the stretch for seconds and repeat 2-5 times for the best results. Here are some common stretches for you to practise. Calf Stretch Standing Hip Flexor Stretch Kneeling Australian Institute of Fitness 40 / 42

41 Quadriceps Stretch Standing Hamstring Stretch Standing Upper Back Stretch Australian Institute of Fitness 41 / 42

42 Chest/Pectorals Stretch Child s Pose / Lower Back Stretch Australian Institute of Fitness 42 / 42