Anatomy 1 PDF - Locomotor System

JAYDEN SARICH FIG 1 ONLINE LEARNING FIG 1 ANATOMY 1 Table of contents We will learn the anatomy of the locomotor system. - Skeletal system - Articular system - Muscular system Surface vs systemic anatomy Surface – anatomical landmarks on the surface of the body through visuali...

JAYDEN SARICH FIG 1 ONLINE LEARNING FIG 1 ANATOMY 1 Table of contents We will learn the anatomy of the locomotor system. - Skeletal system - Articular system - Muscular system Surface vs systemic anatomy Surface – anatomical landmarks on the surface of the body through visualization and palpation Systemic – structure of specific systems of the body such as the nervous or respiratory systems FIG 1 ANATOMY 1 ANATOMICAL DIRECTIONAL TERMS FIG 1 ANATOMY 1 FIG 1 ANATOMY 1 SHOULDER JOINT MOUVMENTS PLANES AND AXIES OF MOUVEMNT Transverse axis – example forwards and backwards roll Sagittal axis – example cartwheel to star Longitudinal axis – example jump full turn Front or coronal plane – divides the body into front and back FIG 1 ANATOMY 1 Sagittal plane – divides the body into 2 sides Movement in the sagittal plane Transverse plane – divides the body into top and bottom BONE STRUCTURE, FUNCTION AND NAMES Compact bone - is the solid, hard outside part of bones. Cancellous (spongy) bone is found at ends of long bones, inside the compact bone. Bones are covered on the outside by a fibrous membrane, the PERIOSTEUM, to which tendons and ligaments will attach. There are 2 kinds of bones Long bones – located in the limbs Short bones – in the skull, spine, pelvis, wrist and ankle FIG 1 ANATOMY 1 MAIN BONES THE STRUCTURE OF BONE - Supports soft tissues and provides attachment for skeletal muscles. - Protects internal organs. - Provides movement together with skeletal muscles. - Stores and releases minerals. - Contains red bone marrow, which produces blood cells. - Contains red bone marrow, which stores fat. FIG 1 ANATOMY 1 MAJOR BONES OF THE BODY PELVIS FIG 1 ANATOMY 1 JOINTS – GENERAL, MOVMENTS Joints in general 1. Slightly Moveable 2. Moveable THE STRUCTURE OF SLIGHTLY MOVEABLE JOINTS - The joints only move slightly - Bones sometimes separated by fibro-cartilage pad o Intervertebral joints o Pubic symphysis - Bones sometimes separated by ligament radius and ulna, distal tibia and fibula FIG 1 ANATOMY 1 THE STRUCTURE OF MOVEABLE (SYNOVIAL) JOINTS MOVEABLE JOINTS (SYNOVIAL) - Many types (hinge, gliding, ball and socket, saddle) - Vulnerable to sprains and dislocations - All human movement occurs as a result of rotations of skeletal segments about joints - Movement of body segments can be described mechanically as occurring o In specific planes o About specific axes (joints) FIG 1 ANATOMY 1 FIG 1 ANATOMY 1 MOVMENTS OF HAND AND WRIST MOVMENT ABOUT THE ELBOW MOVMENT OF THE FOREARM FIG 1 ANATOMY 1 MOVMENT ABOUT THE SHOUDLDER FIG 1 ANATOMY 1 MOVMENT ABOUT THE HIP MOVMENT ABOUT THE KNEE FIG 1 ANATOMY 1 MOVMENT ABOUT THE ANKLE Demonstrated plantar flexion - Toe / foot point - Heel raises Demonstrated dorsiflexion - Hook toe / foot FIG 1 ANATOMY 2 TABLE OF CONTENTS - Specific joints - Cartilage - Tendons and ligaments WRIST JOINT The wrist joint is formed by Distally – the proximal row of carpal bones (except the pisiform) Proximally – the distal end of the radius, and the articular disk The ulna is not part of the wrist joint, it articulates with the radius, just proximal to the wrist joint, at the distal radioulnar joint. Together, the carpal bones form a concave surface with articulates with the convex surface of the radius and the articular disk. The wrist is an ellipsoidal (condyloid) type synovial joint allowing for movement along the two axes, flexion / extension and adduction / abduction the movements of the wrist are performed by the muscles of the forearm FIG 1 ANATOMY 2 ELBOW JOINT The elbow joint is where the long bone at the top of your arm (humerus) meets the 2 bones in the forearm (radius and ulna) It is classified as a synovial hinge joint, and it allows you to bend your arm. The upper part of the radius can rotate so you are able to twist your forearm. The ulnohumeral joint or trochlear joint is composed of the 2 bones (humerus and ulna) and is the junction between the trochlea notch of the ulna and the trochlea of humerus. It is classified as a hinge joint which allows for movements of flexion, extension and circumduction. The radioulnar joints are 2 locations in witch the radius and ulna articulate in the forearm - Proximal radioulnar joint – located near the elbow. It is and articulation between the head of the radius and the radial notch of the ulna. - Distal radioulnar joint – located near the wrist. It is an articulation between the ulnar notch of the radius and the ulnar head Both joints are classified as pivot joints, responsible for the pronation and supination of the forearm. FIG 1 ANATOMY 2 SHOUDLER JOINT The shoulder joint (Glenohumeral joint) is a ball and socket joint between the scapula and the humerus. It is the major joint connecting the upper limbs to the trunk. It is one of the most mobile joint sin the human body, but this makes the joint less stable. The shoulder joint is formed by the articulation of the head of the humorous with the glenoid cavity (fossa) of the scapula. Like most synovial joints the articulating surfaces are covered with hyaline (articular) cartilage The head of the humerus is much larger than the glenoid fossa, giving the joint a wide range of movement at the cost of inherent instability. To reduce the disproportion in surfaces the glenoid fossa is deepened by a fibrocartilage rim called the glenoid labrum (lips) GLENOID LABRUM – a fibrocartilaginous ridge surrounding the glenoid cavity. It deepens the cavity and creates a seal with the head of the humorous reducing the risk of dislocation. SHOUDLER MOVMENTS - EXTENSION - arm moves backwards in sagittal plane - FLEXION - arm moves forwards in sagittal plane - ABDUCTION - arm moves away from midline in frontal plane - ADDUCTION - arm moves towards midline in frontal plane - INTERNAL ROTATION - rotation towards the midline, so that the thumb is pointing medially. - EXTERNAL ROTATION - rotation away from the midline, so that the thumb is pointing laterally. FIG 1 ANATOMY 2 SPINE There are 2 types of joints in the spine The vertebral bodies are joined by inter-vertebral discs made of fibrocartilage and thereby structurally form a symphysis type of cartilaginous joints Each vertebra also has 4 articular processes (2 above and 2 below) which join the vertebrae above and below via synovial joints (facet joints) All vertebrae also protect the delicate spinal cord and nerves within their vertebral canal SPINE INTER-VERTEBRAL JOINTS CERVICAL The cervical spine has 7 stacked bones called vertebrae labelled C1 to C7 The top of the cervical spine connects to the skull and the bottom connects to the thoracic vertebrae at the about shoulder level The cervical spine forms a lordotic curve by gently curving towards the front of the body and the back Roles of the cervical spine - Protecting the spinal cord - Supporting the head and its movements - Facilitating and protecting flow of blood to the brain THORACIC The thoracic spine is the second segment of the vertebral column located between the cervical and lumbar vertebral segments. Is consists of 12 vertebrae which are separated by intervertebral discs Along with the sternum and the ribs the thoracis spine forms part of the thoracic cage The bony structure helps protect the internal organs FIG 1 ANATOMY 2 CHARACTERISTIC FEATURES Vertebra body is heart shaped Presence of demi-facets on the sides of each vertebral body these articulate with the heads of the ribs Presence of costal facets on the transverse processes these articulate with the tubercles of the ribs The spinous processes are long and slant inferiorly this offers increased protection to the spinal cord Thoracic spine is considered to have a restricted range of motion (ROM) compared with that of the cervical and lumbar spine The ROM of the thoracis spine is restricted by the rib cage LUMBAR The lumbar vertebrae consist of 5 individual cylindrical bones that form the spine in the lower back These vertebrae carry all of the upper body’s weight while providing flexibility and movement to the trunk region As in other regions of the spine the movements of the lumbar spine are - Flexion / extension - Lateral bending - Rotation While lumbar motion is potentially greater than that of the thoracic spine because of the lack of rib restriction, facet facing and heavy ligaments check the range of rotatory motion FIG 1 ANATOMY 2 SPECIFIC JOINTS THE PELVIS JOINTS The joints of the pelvis include - Sacrococcygeal - Lumbosacral - Pubic symphysis - Sacroiliac The lumbosacral joints forms from the 5th lumbar vertebrae and the sacrum In between the articular processes this joint has an intervertebral disc The sacrococcygeal joint is a fusion of the bone between the sacrum and coccyx It also consists of an intervertebral disc between the 2 vertebrae and several accessory ligaments The sacroiliac joints are synovial articulations between the surfaces of the ilium and sacrum on either side The sacroiliac joints surface is smooth and flat and has posterior strengthening by dorsal sacroiliac and interosseous ligaments When a person is upright the body weight usually transmits to the sacrum and iliac When sitting or supine the persons body weight transmits to the ischial tuberosity The pubic symphysis is a cartilaginous joint located between the main body of the pubic bone in the anterior midline. This joint is covered with hyaline cartilage and the ligaments around it are flexible and relax during pregnancy FIG 1 ANATOMY 2 HIP JOINT A cartilaginous labrum expands the size of the bony socket It can be distorted and damaged at extreme ranges of hip motion KNEE JOINT The knee joint is a hinge type synovial joint which mainly allows for - Flexion / extension - Small degree of medial and lateral rotation It is formed by articulations between the patella, femur and tibia KNEE LIGAMENTS Ligaments are bands of strong tissue that connect bone to bone The knee has 4 major ligaments that connect the femur to the tibia - Anterior cruciate ligament (ACL) - Posterior cruciate ligament (PCL) - Medial collateral ligament (MCL) - Lateral collateral ligament (LCL) The ACL and PCL prevent the femur and tibia from sliding too far forwards and backwards The MCL and LCL prevent side to side movement FIG 1 ANATOMY 2 A knee meniscus is a thick pad of cartilage located between the femur and tibia There are 2 menisci in each knee - Medial meniscus (located on the inside of the knee) - Lateral meniscus (located on the outside of the knee) The menisci reduce shock and absorb impact when moving or bearing weight Also helps stabilize the knee and facilitate smooth motion between the surface of the knee THE ANKLE JOINT Ankle joint is formed by 3 bones - Tibia - Fibula - Talus (in foot) The tibia and fibula are bound together by strong tibiofibular ligaments Together they form a bracket shaped socket, covered in hyaline cartilage. This socket is known as mortise The body of the talus fits snugly into the mortise formed by the bones of the leg. The articulating part of the talus is wedge shaped – it is broad anteriorly and narrow posteriorly DORSIFLEXION – the anterior part of the talus is held in the mortise and the joint is more stable PLANTARFLEXION – the posterior part of the talus is held in the mortise and the joint is less stable The ankle joint is a hinge type joint with movement permitted in one plane FIG 1 ANATOMY 2 The plantarflexion and dorsiflexion are the main movements that occur at the ankle joint Eversion and inversion are produced at the other joints of the foot, such as the subtalar joint PLANTARFLEXION is produced by the muscles in the posterior compartment of the leg (gastrocnemius, soleus plantaris and posterior tibial) DORSIFLEXION is produced by the muscles in the anterior compartment of the leg (tibialis anterior, extensor hallucis longus and extensor digitorum longus) The medial ligament is attached to the medial malleolus (a bony prominence projecting from the medial aspect of the distal tibia) Is consists of four ligaments, which fan out from the malleolus, attaching to the talus, calcaneus and navicular bones The primary action of the medial ligaments is to resist over eversion of the foot The lateral ligament originates from the lateral malleolus (a bony projecting from the lateral distal fibula) It resists over inversion of the foot and is comprised of 3 distinct and separate ligaments - Anterior talofibular - Posterior talofibular - Calcaneofibular FIG 1 ANATOMY 2 TYPES OF CARTILAGE - Articular cartilage - Growth cartilage - Fibrocartilage ARTICULAR, GROWTH AND FIBROCARTILAGE ARTICULAR (HYALINE) CARTILAGE Is a connective tissue covering the end of bones that functions as a load bearing, low-friction, and wear-resistant surface to facilitate joint movement Provides smooth articular surfaces for movable (synovial) joints. It protects through shock absorbing. Has poor regenerative (healing) capacity. Damage can lead to degeneration of tissue. Mainly subjected to compression forces. GROWTH CARTILAGE (PHYSIS OR GROWTH PLATE) Responsible for growth in height. Fuses (ossifies) in late teens resulting in cessation of growth. bumps (tubercles) on bones for tendon attachment also have growth plates. FIBROCARTILAGE Provides articular pad for some movable joints Provides tough union between structures Examples of fibrocartilage pads in joints - Between ulna and metacarpals - Between vertebrae - Lateral and medial meniscus cartilage FIG 1 ANATOMY 2 LIGAMENTS Strong rope like tissue joins bone to bone Ligamentous joint capsule surrounds (encapsulates) movable (synovial) joints Capsule is also reinforced with ligaments There are some ligaments within joints (eg knee and hip) In joints between long bones of the limbs there are often thick ligaments on each side of the joint (collateral ligaments) TENDONS Strong rope like tissue that joins muscle to bone Inverts into the periosteum of bone with some fibbers actually interwoven into bone matrix Sometimes in sheets called fascia Some tendons also serve as joint stabilizers (rotator cuff of the shoulder) FIG 1 ANATOMY 2 COMMON INJURIES AND DISEASES IN MAG - Osgood-Schlatter disease - Servers disease - Injuries to knee ligaments during under rotation on longitudinal axis - Injuries to ankles during under rotation on transversal axis FOREARM SPLITS Forearm splints are painful and frustrating injuries that occur most often in athletes, gymnasts, and weight trainers. This injury is due to tendons that are unable to stand the stress that is being placed on them. These tissues tear away from the bone or bones that they are attached to. This is very similar to shin splints, and generally take about the same amount time to heal. Interosseous membrane between radius & ulna (forearm). SHIN SPLINTS The term “shin splints” describes pain felt along the front of your leg and shinbone. You’ll notice the pain in the front area of the leg between your knee and ankle. Shin splints are a common overuse injury. They can occur from running or doing other high-impact activities for extended periods of time or without adequate stretching. FIG 1 ANATOMY 2 GYMNAST WRIST Gymnast wrist is an overuse injury that can occur in adolescent gymnasts. It is a combination of injuries to the bone and the ligaments of the wrist. Gymnast wrist occurs because of the repetitive compressive forces applied across the wrist during the weight bearing activities of gymnastics. Gymnast wrist is commonly shown as a chronic stress fracture of the distal radius, and in these skeletally immature gymnasts, this is near the growth plate of the wrist. SHOULDER INJURIES – IMPINGEMENT Shoulder impingement - when the tendons of the rotator cuff (RTC) become trapped and compressed under the bones (humerus and acromion) during shoulder movements. The shoulder is unusual because unlike most areas of the body, the bone covers the muscle. The rotator cuff muscle is sandwiched between the humerus (arm bone) and the acromion (top of the shoulder) in an area called the subacromial space. The rotator cuff (RTC) can become pinched between these bones leading to injury and inflammation (tendonitis and bursitis). FIG 1 BIOMECHANICS 1 TABLE OF CONTENTS - Kinetics - Kinematics - Static positions - Applied biomechanics WHAT IS BIOMECHANINCS Application of mechanical laws to living structures Study of forces acting on or produced by human bodies (external or internal forces) Biomechanics applies to the technique realm KINETICS – is the study of the relationship between the force system acting on a body and the changes it produces in a body motion KINEMATICS – is a branch of mechanics that deals with the geometry of the motion of objects, including displacement, velocity and acceleration without taking into account the forces that produce the motion APPLICATION: USES OF BIOMECHANICS KNOWLEDGE - Understanding gymnastics skills - Analysing and teaching skills - Identifying causes of errors - Correcting errors - Applications to changes in apparatus/rules - Innovate(or evaluate new innovations) FIG 1 BIOMECHANICS 1 EXAMPLE 1 OLD VAULT TABLE The old vaulting horses had significant safety and mechanical disadvantages NEW VAULT TABLE ADVANTAGES - Increased approach velocity - Shorter pre-flight times FIG re-evaluated and changed the ''Vaulting Horse'' by the ''Vaulting Table'', citing both safety reasons and the desire to facilitate more impressive acrobatics. The 2001 World Artistic Gymnastics Championships were the first international competition to make use of the "vaulting table". It features a flat, larger, and more cushioned surface almost parallel to the floor, which slopes downward at the end closest to the springboard; it appears to be somewhat safer than the old apparatus. New vault table = more effective force application New table - safer and more comfortable wrist position - advantage for applying vertical forces - increased friction (safety and force application) FIG 1 BIOMECHANICS 1 TYPES OF BIOMECHANICAL ANALYSIS 2 different prospective analyses - quantitative biomechanical analysis - qualitative biomechanical analysis QUANTITATIVE BIOMECHANICAL ANALYSIS It is generally used for scientific studies since it requires more preparation time, more technological resources for data collection and often laborious statistical analysis QUALITATIVE BIOMECHANICAL ANALYSIS Useful and easy to - identify movement parameters and deviations - describe positions and phases, actions - explain causes, mechanisms, principles - Predict effects, techniques, methodologies - Recommend physical or technical corrections FIG 1 BIOMECHANICS 1 KINETICS Force – can be considered as the pushing or pulling action that one object exerts on another A force is any cause that changes or tends to change the velocity or shape of an object The international system of units (SI) unit of force is the newton (N) and the symbol for a force vector is (F) Gymnasts experience forces both internal to and external to the body Internal forces are generated by the muscles and transmitted by tendons, bones, ligaments and cartilage The main external forces are - Weight - Reaction forces - Friction Their combined effect determines the overall motion if the body EXTERNAL FORCES - Force of gravity (weight) - Centripetal force - Ground reaction force - Frictional force - Impulse force - Torque RESULTANT FORCE If a number of forces act simultaneously their combined effect can be represented by a single force known as the resultant force In gymnastics more than one force usually acts on the performer and the effect produced by the combination of these forces will depend on their magnitudes and relative directions = resultant forces FIG 1 BIOMECHANICS 1 NEWTONS LAW OF MOTION FIRST LAW OF MOTION – LAW OF IINERTIA A body at rest will remain at rest and body of motion will remain in motion unless it is acted upon by an external force The fact that massive bodies resist changes in their motion is sometimes called inertia A body will remain at rest or in uniform motion in a straight line unless it is acted upon by an external force The greater the resistance to change (inertia) the greater the force needed to change the motion of an object (accelerate or decelerate it) The greater the momentum (mass x velocity) the greater the force needed to change the velocity of the object INERTIA AND LINEAR MOMENTUM INERTIA - the reluctance of a body to alter its state of rest of motion - it is the related to the mass of the body LINEAR MOMENTUM - a measure of the total ‘quantity’ of motion that a body has - it is related to the mass and the velocity of the body - linear momentum = MASS X VELOCITY the linear measure of inertia is mass and has units of kg in the international system if units (SI) FIG 1 BIOMECHANICS 1 In angular kinetics, inertia is measured by the moment if inertia The formula of a rigid body moment of inertia about an axis (A) is IA=m - r2 SECOND LAW OF MOTION (LAW OF ACCELERATION) The force action on an object is equal to the mass of the object times its acceleration. This is written in mathematical form as F=m.a where F is force, M is mass and A is acceleration THIRD LAW OF MOTION (LAW OF ACTION) For every action force there is a reaction force that is - equal in magnitude - opposite in direction - simultaneous Force always acts in pairs FIG 1 BIOMECHANICS 1 PRINCIPLE OF ACTION – REACTION IN THE AIR It is not possible to move body part A towards body part B without simultaneously moving body part B towards body part A This is the basis for generating ‘indirect’ ground reaction forces when in contact with the floor or apparatus When a body part is extended upward, the body must move downward and vice versa When a body part is extended sideways the body must tilt in the opposite direction When the legs are extended forwards the trunk must come forwards and vice versa When the upper body is twisted to the right the lower body must twisted to the left and vice versa KINEMATICS VELOCITY Measure of how far the body has moved a specific period of time (average velocity) or of how fast it is moving (instantaneous velocity) It is usually measured in meters per seconds (m/s) FIG 1 BIOMECHANICS 1 ACCELERATION Acceleration is a measure of how much a body’s velocity changes over time An increase in velocity is acceleration and a decrease is negative acceleration or deceleration A change in direction is an acceleration. It is measured in meters per second per second (m/s2) A change of velocity requires the application of a force Therefore acceleration is a measure of the force applied (F= m x a) If a body slows down, speeds up or changes direction, a force must be the cause In the air the only force acting is the force of gravity Vertical force = gravity (g=9.81 m/s2) which causes acceleration downward Horizontal force = 0 there is no horizontal acceleration FIG 1 BIOMECHANICS 1 BIOMECHANICS GYMNASTICS REASEARCH EXAMPLE In the example below, we see a biomechanical study that investigates the relationship between running speed and jump quality (verified by the final grade). Among the conclusions of the study, the authors highlight: "[...], this study confirmed that a high run-up speed is one of the most important determining factors to succeed on vault in women’s and men’s artistic gymnastics competition." STATIC POSITIONS WEIGHT AND MASS DEFINITION MASS - quantity of matter that an object contains - it is always the same everywhere in the universe - measure of an objects inertia or reluctance to change its state of rest or motion - mass is a measure of quantity (Kg) WEIGHT - the gravitational attraction between 2 objects - larger mass – larger gravitational attraction (therefore it can vary with location) - Weight is a measure of force (Newton N) FIG 1 BIOMECHANICS 1 FORCE OF GRAVITY The force of attraction between any 2 masses On earth it is experienced as a force acting vertically downwards through the centre of mass The downward force is approximately 10m/s2 (9.81m/s2) The force measured as weight (N) The force of 1 body weight is often referred to as 1g (3g’s=3 x body weight) CENTER OF MASS / CENTER OF GRAVITY (COM) Is the point about which a body is equally balanced in all directions The point of intersection of the 3 principal axes - Longitudinal - Transverse - Anterior / posterior The point at which the body’s total mass is considered to be concentrated Therefore it is a point as which the force of gravity is considered to act Important – the centre of mass can be out side the body In the anatomical position - COM is at 57% standing height of males - COM is at 55% standing height of females The location of COM changes when we move. The COM is calculated to investigate mechanics of bodies in motion or in stable positions FIG 1 BIOMECHANICS 1 PRINCIPLES OF STABILITY – STABILITY AND BALANCE STABILITY – the resistance to linear and angular motion BALANCE – the ability to maintain a stable position PRINCIPLES OF STABILITY the lower the COM to the base of support, the greater the stability. The larger the base of support, the greater the stability. The nearer the COM is over the centre of the base of support, the greater the stability. In a segmented body, the better the vertical alignment of the COM’s of the individual segments, the greater the stability. 1. THE LOWER THE COM TO THE BASE OF SUPPORT THE GREATER THE STABILITY 2. THE LARGER THE BASE OF SUPPORT THE GREATER THE STABILITY FIG 1 BIOMECHANICS 1 3. THE NEARER THE COM IS OVER THE CENTER OF THE BASE OF SUPPORT THR GREATER THE STABILITY 4. IN A SEGMENTED BODY THE. BETTER THE VERTICAL ALIGNMENT OF THE COMS OF THE INDIVIVDUAL SEGMENTS THE GREATER THE STABILITY FIG 1 BIOMECHANICS 1 APPLIED BIOMECHANICS See some practical examples of the use of the principles of biomechanics to better understand gymnastics – indirect ground reaction forces The reaction to a ‘direct action’ force applied by the gymnast is called a ‘direct ground reaction force’ The reaction to a ‘reaction action’ applied by the gymnast is called an ‘indirect ground reaction force’ 1. Jumping – downwards pushing the legs results (F ACTION) in an upwards direct (GROUND) reaction force (F REACTION) 2. Swinging arms up (DIRECT ACTION) body wants to go down (DIRECT REACTION) and increases reaction force upward (INDIRECT REACTION FORCE) FIG 1 BIOMECHANICS 1 MECHANICS OF SPRING An action force must be applied that generates a reaction force large enough to overcome the force of gravity Can be from internal forces (muscular contractions) Can be from external forces (mini tramp, bar, springboard ect) Effective force application is related to - Magnitude - strength in all active muscles - Point of application - (off centre = rotation) - Direction - always opposite to application - Duration - range of motion/flexibility - Timing – coordination - Rigidity of the body - body tension & shape MAGNITUDE OF FORCE - Must be sufficient for the desired outcome (optimal vs maximal). - Strength & power in all active muscles. DIRECTION OF FORCE - Must be in the desired direction. - Remember “action force > reaction force”. DURATION OF FORCE - Must be over the longest time and distance possible. - range of motion/flexibility in all active joints. TIME OF FORCE - Sequential summation of forces - Largest to smallest - Proximal to distal - Coordination FORCE APPLIED TO RIGID BODY - Otherwise forces will be used or “wasted” to change the shape of the body. - Body tension & shape. FIG 1 BIOMECHANICS 1 at the instant of take off these are determined - Angle (º) of take-off and landing (COM) - Vertical velocity up (Vz) (reduced to zero by gravity) - Vertical velocity (Vz) on landing = Initial vertical velocity (V0z). - Horizontal velocity (Vx) - Height (= Time) - Distance - Direction Time in the air (= Height) ROTATIONAL MOMENTUM - Body shape (= potential to change speed of rotation) TOTAL MECHANINCAL ENERGY - Total Mechanical Energy (= Potential Energy + Kinetic Energy) FIG 1 BIOMECHANINCS 2 TABLE OF CONTENT - Projectile motion - Rotation - Swing - Landing PROJECTIVE MOTION TRAJECOTORY As soon as a body is in the air the force of gravity continuously acts downwards to change its velocity and direction - It accelerates downwards - Its horizontal velocity remains constant The centre of mas of an object follows the path of a parabola After release or take off (human or portable apparatus) the path (trajectory) of the centre of mass cannot be changed The shape of the path depends on - Angle of take-off / release - Height of take-off / release - Velocity of take-off / release Therefore, it is essential to maximize these parameters during take- off or release HOW THIS CONCEPT APPLIES TO GYMNASTICS FIG 1 BIOMECHANINCS 2 TAKE OFF At any take off velocity the angle of take-off from the apparatus will determine the shape of the flight parabola (the trajectory of the COM) - A steep take-off angle will produce a high flight with small horizontal travel - A shallow take-off angle will produce a low flight with large horizontal travel At the instant of take-off these are determined - Path of centre of mass (trajectory) - Angle of take-off and landing (of C of M) - Vertical velocity up (reduced to zero by gravity) - Vertical velocity on landing = initial vertical velocity - Horizontal velocity - Height (= time) - Distance - Time in air (= height) Most errors occur at take-off and are usually due to incorrect force application The centre of mass of a rigid body will fly at a tangent to the arc of the swing (90° to the radius) This is an important consideration, but gymnast can apply forces just before release to somewhat modify this effect In addition, the elasticity of the bar can modify the effect FIG 1 BIOMECHANINCS 2 DISMOUNT Releasing below horizontal - High vertical - Small horizontal WINKLER Releasing too horizontal - Maximum vertical - No horizontal KOVACS Releasing above horizontal - Flight path over the bar ROTATION The main concepts you need to know to understand the mechanics of rotation are MOMENT OF INERTIA (ROTATIONAL INERTIA) MOMENT OF INERTIA – it is a measure of the distribution of mass about the axis of rotation - If the mass is far from the axis the moment of inertia is large - If the mass is close from the axis the moment of inertia is small FIG 1 BIOMECHANINCS 2 ANGULAR VELOCITY (ROTATIONAL VELOCITY) It is the speed of rotation about the axis of rotation ANGULAR MOMENTUM (ROTATIONAL MOMENTUM) It is the total quantity of rotation about the axis of rotation Angular momentum is conserved (does not change) in the air With the straight body the distribution of mass is furthest from the transverse axis - The moment of inertia is large relative to the axis of rotation - There is a high resistance to a turning motion - A large force is necessary to smart or stop the rotational movement With a tucked body the mass us bought close to the transverse axis - The moment od inertia is small relative to the axis of rotation - There is less resistance to a turning motion - A small force is necessary to start or stop the rotational movement FIG 1 BIOMECHANINCS 2 With a straight body (frame 4 & 5) the distribution of mass is furthest from the transverse axis - The moment of inertia is large relative to the axis of rotation - There is a high resistance to a turning motion With a tucked body (frame 6 & 7) the mass is brought close to the transverse axis - The moment of inertia is small relative to the axis of rotation - There is less resistance to a turning motion Angular momentum is conserved (stays the same) in the air If the rotational momentum is set, then nothing the gymnast does can change the total But the gymnast can change the body shape which is equivalent to changing the moment of inertia (straight to tuck position; bring arms close to the body during twisting elements) For the rotational momentum to stay the same the change in shape (moment of inertia) must be accompanied by an opposite change in speed or rotational (angular velocity) - Decrease / shorten the shape = increase speed - Increase / lengthen the shape = decrease speed FIG 1 BIOMECHANINCS 2 HOW DO WE GENERATE ANGULAR MOMENTUM (ROTAION) We can generate angular momentum (rotation) by creating torque (turning force) In a simplified way, torque is a measure of the turning force on an object such as a bolt EXAMPLE – pushing or pulling the handle of a wrench connected to a nut or bolt produces a torque (turning force) that loosens or tightens the nut or bolt Torque = Force x Distance To generate torque (turning force) you need to create - An off centre (ground reaction) force - Maximum distance from the axis - A force couple SIDE NOTE – opening and closing a door works on the principle - This is why a door handle is placed maximum distance from the hinge - When you push the door you are creating an off centre force maximum distance from the axis FIG 1 BIOMECHANINCS 2 HOW THIS CONCEPT APLLIES TO GYMNASTICS To generate torque (turning force) the gymnast needs to create To generate more torque (turning force) in a longitudinal axis rotation the gymnast needs to create a “off centre force” using the arms To generate more torque (turning force) for a transversal axis rotation (salto) the gymnast needs to create A gymnast must maximize angular momentum during the take-off phase in order to maximize the possible effect of changing his body shape FIG 1 BIOMECHANINCS 2 HOW DO WE GENERTAE ANGULAR MOMENTUM (ROTATION) Effective force application in order to generate angular momentum during take-off is related to - MAGNITUDE – maximum (optimum) off-centre force - POIINT OF APPLICATION – applied as far as possible from axis of rotation - DIRECTION – always opposite to application - DURATION – applied throughout take-off phase - TIMING – large to small proximal to distal - RIGIDITY OF THE BODY – body tension and shape ANGULAR MOMENTUM (ROTATION) – TAKE OFF At the instant of take-off there are determined - Path of centre of mass (trajectory) - Angle of take-off and landing (of COM) - Vertical velocity up (reduced to zero by gravity) - Vertical velocity on landing = initial vertical velocity - Horizontal velocity - Height (= time) - Distance - Direction - Time in the air (= height) - Angular Momentum (body shape = potential to change speed of rotation) Most errors occur at take-off and are usually due to incorrect force application FIG 1 BIOMECHANINCS 2 EXAMPLE OF SLATO FORWARDS EXAMPLE OF SLATO BACKWARDS EXAMPLE OF 2/1 TURN TUCK JUMP FIG 1 BIOMECHANINCS 2 THE COMBINATION OF ROTATION CONCEPTS Torque and the change in shape (moment of inertia) accompanied by an opposite change in speed of rotation (angular velocity) in a jump air turn MORE ABOUT THE TAKE-OFF PHASE The take-off phase is critical most errors occur here The path of centre of mass (trajectory) in flight is determined Nothing the gymnast does in the air can change the path of the centre of mass The total body angular momentum (rotation) in flight is determined Nothing the gymnast does in the air can change the angular momentum of the body SWING Swing is the rotation about an external axis MECHANICS OF ROTATION: SWING The gymnast should maximize (optimize) angular momentum at bottom of swing - On downswing gravity provides the turning force (torque) - Gravity should act over the longest time possible - Gymnast should minimise frictional forces - On upswing the angular velocity is increased by bringing the centre of mass closer to the axis of rotation (bar) FIG 1 BIOMECHANINCS 2 FIG 1 BIOMECHANINCS 2 LANDING LANDING AND ANGULAR MOMENTUM Most the gymnastics landing follow an element with rotation about one or 2 axes The gymnast must be able to complete the twist or salto and extend the body prior to landing. (more height (= time) and more angular momentum -> better force application during take-off) An extending body position prior to landing (5) reduces the angular velocity and provides time to apply forces that reduce the angular momentum to zero (6) it also reduces deductions EFFECTIVE FORCE APPLICATION Effective force application in landing is related to - MAGNITUDE – eccentric strength in all active muscles - POIINT OF APPLICATION – far from axis – to stop rotation - DIRECTION – always opposite to application - DURATION – range of motion / flexibility - TIMING – co-ordination (the reverse of take-off) - RIGIDITY OF THE BODY – body tension and shape FIG 1 BIOMECHANINCS 2 EFFECTIVE FORCE APPLICATION IN ORDER TO GENERATE ANGULAR MOMENTUM DURING TAKE-OFF IS RELATED TO - MAGNITUDE – maximum (optimum) off-centre force - POIINT OF APPLICATION – applied as far as possible from axis of rotation - DIRECTION – always opposite to application - DURATION – applied throughout take-off phase - TIMING – large to small – proximal to distal - RIGIDITY OF THE BODY – body tension and shape CONSIDERING THE IMPORTANCE OF LANDING FRO GYMNASTICS TRAINING AT ALL LEVELS IT IS RECOMMENDED TO LEAR TO LAND IN DIFFERENT WAYS - LANDING ON THE FEET – forwards, backwards and sideways - LANDING ON THE HANDS – forwards, backwards and sideways - LANDING WITH HORIZONTAL MOMENTYM SHOULDER ROLLS – forwards, backwards and sideways - LANDING FLAT ON THE BACK – break falls - INVERTED LANDING FIG 1 BIOMECHANINCS 2 GLOSSARY MASS – The quantity of matter in an object. Mass can be thought of conceptually as the number of atoms in the object that would, of course, remain constant regardless of location or gravitational conditions (eg, earth or moon gravity). Weight, however, would vary under these two conditions. The importance of mass in mechanics is that it represents, in linear terms, the resistance to a change of state (a speeding up or slowing down). Designated as m. WEIGHT – The force that results from the action of a gravitational field on a mass. Weight can be thought of as the force an object exerts on a stationary supporting surface placed perpendicular to a gravitational field (and by Newton's third law as the force the surface exerts on the object). Side note: When we "weigh" ourselves, we are determining weight not mass, but if the gravitational field is the same (the acceleration resulting from gravity does not change), mass can be estimated from weight using Newton's second law. CENTRE OF MASS – The point on a body that moves in the same way that a particle subject to the same external forces would move. Side note: The centre of mass is not necessarily located in the body. Designated as CM or CoM. CENTRE OF GRAVITY – The point at which a single force of magnitude (the weight of the body or system) should be applied to a rigid body or system to balance exactly the translational and rotational effects of gravitational forces acting on the components of the body or system. In other words, the point at which the weight of the body or system can be considered to act. Side note: For all practical purposes, the centre of gravity and the centre of mass are coincident, although in strict physical terms, there is an infinitesimal difference between the two. DISPLACMENT – The change in the position of a body. This change may be translations, whereby every point of the body is displaced along parallel lines; it may be rotational, with the points of the body describing concentric circles around an axis; or it may be a combination of the two. For example, although the general movement of the human body during locomotion is translations, the limbs act with rotatory motion around many joints to obtain this result. As linear unit we use meters (m). VELOCITY – A measure of a body's motion in each direction. Because velocity has both magnitude and direction, it is a vector quantity that can be positive, negative, or zero. Linear velocity is the rate at which a body moves in a straight line. Mathematically, velocity is the first derivative with respect to time of displacement and the first integral with respect to time of acceleration. As units we use m/s. FIG 1 BIOMECHANINCS 2 ANGULAR VELOCITY – The rate of movement in rotation calculated as the first time derivative of angular displacement. ACCELERATION – The rate of change of velocity with respect to time, mathematically the second time derivative of displacement and the first time derivative of velocity. Acceleration is also a vector quantity that may take positive, negative, or zero values. As unit we use m/s2. LEAVER – A lever is a system that tends to change the mechanical advantage of an applied force. Basically, it consists of two forces and a fulcrum or hinge. The two forces are called an effort force (such as a muscular force) and a resisting force (such as a weight held in the hand or a ground reaction force). The perpendicular distance of each force from the fulcrum is called the lever arm. FORCE – A vector quantity that describes the action of one body on another. The action may be direct, such as the foot pressing on the floor, or it may be indirect, such as the gravitational attraction between the body and the earth. Force can never be measured directly. It is always estimated, for example, by measuring the deflection of a spring under the action of a force. As unit we use N (newton). MOMENT – The turning effect produced by a force. Calculated as the product of the force and the perpendicular distance between the point of application of the force and the axis of rotation. In vector terms, the calculation is the vector (cross) product of force and distance. We use n.m (newton x meter). ANGULAR MOMENTUM – The rotational equivalent of linear momentum that can be thought of as describing the "amount of motion" that the body possesses during rotation. Computationally, it is the product of the moment of inertia and the angular velocity. MOMENT OF INERTIA – The rotational equivalent of mass in its mechanical effect, that is, the resistance to a change of state (a speeding up or slowing down) during rotation. Intuitively, this would appear to be dependent on the mass of the object and the way the mass is distributed. In fact, the effect of distribution of mass is dominant as the following formula indicates: I= m.r2 where m = mass and r = distance from axis of rotation. NEWTONS LAWS OF MECHANICS Three laws that form the basis of conventional or Newtonian Mechanics. The laws can be remembered by the acronym IN-MO-RE: 1) first law of Inertia, 2) second law of Momentum, and 3) third law of Reaction. Newton's first law states that a body will maintain a state of rest or uniform motion unless acted on by a net force. Newton's second law states that the change in momentum of the body under the action of a resultant force will be proportional to the product of the magnitude of the force and the time for which it acts (ie, the impulse).The second law also states that the change in momentum will be in the direction of the resultant force. Newton's third law states that action and reaction are equal and opposite. Although the first and third laws are somewhat intuitive, the second law provides a means for: FIG 1 BIOMECHANINCS 2 1) the formulation of equations of motion, 2) the definition of units of force, and 3) the formulation of the impulse momentum relationship. The second law is frequently stated as, "Force equals mass times acceleration" (F = m∙a). WORK – Work is done when a force moves an object through a distance. Whenever a constant force exists and motion takes place in a straight line, then work equals the magnitude of the force (F) times the distance (d) through which the object moves: W = F.d. Side note: According to this definition, no mechanical work is done during isometric action of a muscle. As unit we use J (joule). POWER– The rate of doing work. Power is equal to the work done divided by the time during which the work is being done: P = W/t. As unit we use W (watt). ENERGY – The capacity for doing work. In any system, this capacity cannot be destroyed, but energy can be transformed from one form to another (this is a statement of the Principle of Conservation of Energy). In biomechanics, the forms of energy that are most frequently encountered are kinetic energy, potential energy, and heat energy. KINETIC ENERGY – That component of the mechanical energy of a body resulting from its motion. Two forms of kinetic energy are identified. Kinetic energy of translation = ½m∙v2 POTENTIAL ENERGY – That component of the mechanical energy of a body resulting from its position. Potential Energy = m.g.h MECHANICAL ENERGY – The total mechanical energy of a body or system. This total repre- sents the sum of the kinetic energy and the potential energy. FIG 1 PHYSIOLOGY 1 TABLE OF CONTENT - Muscle fibres - Muscle fibre type - Strength, Hypertrophy - Strength, Neural PHYSIOLOGY, MUSCLE FIBER AND STRENGTH All the information in the 4 lectures of physiology in level 1 and 2 intend to give the knowledge to understand the 7 training principles - Adaptation is specific to demand (stimulus) - The magnitude of the stimulus must progressively overload - Adaptations are reversible - Adaptations differ between individuals - Variation – a continued stimulus produces a decrease in response (accommodation) - Insufficient recovery reduces training effect - Expect diminishing adaptation at high levels \MUSCLE FIBER Since muscle tissue is that cause of all movements, it follows that we should understand how muscle tissue functions SKELETAL MUSCLE – (VOLUNTARY) - Multi-nucleated, cylindrical cell - Maximum length 12cm (4.5in) - Diameter of a thin human hair FIG 1 PHYSIOLOGY 1 Each fibre is made of bundles of cylindrical myofibrils Each myofibril is made up of rod-like proteins (contractile proteins) The central protein myosin is surrounded at each end by a bundle of 6 actin ‘rods’ FIG 1 PHYSIOLOGY 1 PHYSIOLOGY - MUSCLE FIBER AND STRENGTH Actin forms the framework of a functional unit called a sarcomere The sarcomere is the ‘functional unit’ of the muscle fibre. It is one z-line to the other z- line MUSCLE CONTRACTION A muscle contraction involves thousands of sarcomeres shortening (actin sliding over myosin) FIG 1 PHYSIOLOGY 1 ORGANIZATION OF SKELETAL MUSCLE From the gross to the molecular level MUSCLE FIBER TYPES HOW MUSCLES ATTACH TO BONE Each muscle fibre and all bundles of muscle fibres are covered by connective tissue (comprised mainly of the protein collagen) All these ‘coverings’ join to form the tendons that join muscles to bones (to the periosteum membrane around the bone) 2 DIFFERENT TYPES OF MUSCLE FIBRES FAST TWITCH FIBRES – contract very quickly but they fatigue quickly SLOW TWITCH FIBRES – contract slowly and continue contracting for a long time without fatiguing SLOW TWITCH - 110 milliseconds to reach peak - Fatigue resistance - Innervates approx. – 100 muscle fibres FAST TWITCH - 50 milliseconds to reach peak - Fatigue quickly - Innervates approx. - 500 muscle fibres Thus generates grater force than slow twitch FIG 1 PHYSIOLOGY 1 Muscles that are mostly fast twitch fibres will produce more forceful contractions Muscles that are mostly slow twitch fibres will produce less powerful contractions, but will repeat the contractions many more times before fatigue PHYSIOLOGY, MUSCLE FIBER AND STRENGTH People vary greatly in the proportion of slow and fast twitch fibres in their muscles Those with high ratios of fast twitch fibres will be better at explosive sports and those with high ratio of slow twitch fibres will be better at endurance sports It is possible to train so that fast twitch fibres are selectively recruited by training at high force and or high speed It is possible to train so slow twitch fibres are selectively recruited by training slower speeds at higher repetitions IMPORTANT - people are different in their genetic proportions of muscle fibres - people with high percent of slow twitch can improve their speed by doing high velocity or high force training that will increase synchronization and recruitment of motor units plus intra and inter muscular coordination EXAMPLES OF HIGH-SPEED TRAINING (PHYSCIACL CONDITONING) - jump rope - banded squat and extension over head - med ball throw and catch over head FIG 1 PHYSIOLOGY 1 STRENGTH AND HYPERTROPHY When muscles contract, they generate forces which we call strength Muscular strength refers to the amount of force a muscle can produce with a single maximal effort The maximum force a muscle can generate in 1 contraction, no time limit is also called (1 repetition maximum) HOW CAN WE INCREASE STRENGTH There is one way in increase the amount of contractile proteins (actin / myosin) in the myofibrils This is called hypertrophy We stimulate (or stress) the muscle, and the muscle adapts to this stress by producing more actin & myosin protein, increasing the density of contractile proteins Muscular hypertrophy refers to an increase in muscle mass This is usually manifests as an increase in muscle size and strength We stress the muscle by having it contract against a load To maximize hypertrophy the load must be high enough to fatigue the muscle after approximately 10 reps There is more hypertrophy in mature and developing males because of androgenic (muscle building) hormones FIG 1 PHYSIOLOGY 1 EXAMPLES OF DIFFERENT BODY SHAPES Important – the gymnast body will adapt to the specificity training of the different gymnastics disciplines Strength training must be defined taking into account the different objectives and characteristics of gymnastics and gymnast You will notice that strength training must be designed to meet the different objectives that characterize each of these gymnastics disciplines, while respecting the individual characteristics of each gymnast STRENGTH – NEURAL For a muscle to contract, it needs a ‘drive’ mechanism – a neural impulse Neural impulses are ‘electrical’ currents that pass along nerve fibres Each ‘motor’ (to muscle) nerve innervates many muscle fibres and is called a motor unit FIG 1 PHYSIOLOGY 1 WE CAN INCREASE STRENGTH, BY INCREASING THE NEURAL DRIVE TO THE MUSCLE IN THE FOLLOWING WAYS - increase firing frequency - recruit more motor units - synchronize the firing of motor units - reduce inhibitory firing - improve inter and intra-muscular coordination the above 5 ‘neural’ mechanisms appear to be the main ways of strength gain in all gymnast and specially in early strength training (1st month) and in prepubertal gymnast SO WHERE ARE WE - we can increase muscle strength by hypertrophy (increasing muscle size) - we can increase muscle strength by increasing neural drive to muscles HOW TO USE NEURAL TRAININ TECHNIQUES ON THE FOLLOWING EXERSISES CHIN UP Do only the arm action with some elastic bands (to have small resistance), while standing, but do it very rapidly (after warm-up) so that maximum speed is achieved (with proper technique). Do rapid chin-ups (after warm-up). If athlete can do more than 5, increase the load by holding waist or adding weight vest so that maximum force is achieved. PUSH UP Do only the arm action, while lying prone on narrow bench or with shoulders higher than feet but do it very rapidly (after warm-up) so that maximum speed is achieved. Do rapid push ups (after warm-up). If athlete can do more than 10, increase the load by gently pressing down on gymnasts shoulders so that maximum force is achieved. FIG 1 PHYSIOLOGY 1 HOW CAN WE INCREASE STRENGHT There is one more way to ‘neural’ increase strength (increase strength without increasing muscle size) INCREASE USE OF THE STRETCH REFLEX - if any muscle is quickly stretched, there is a built-in reflex that causes that stretched muscle to contract FIG 1 PHYSIOLOGY 1 INCREAING FORCE USING STRETCH REFLEX - receptors (muscle spindles) that sense muscle stretch are sprinkled throughout skeletal muscle - muscle spindles are very sensitive to the rate of stretch (fast stretch = larger reflexive contraction of muscle) - this reflexive contraction increases the force of an ‘immediately flowing’ voluntary contraction STRETCH REFLEX EXAMPLE TO ENHANCE THE MUSCLE FORCE ON A CHIN UP AND LEG LIFT WHILE HANGING ON A BAR CHIN UP - at the bottom of the chin up slow down & then drop the last 10 cm & bounce into the next chin up. STRAIGHT LEG LIFTS -allow the gymnast rapid arch just before flexing hips. The arch will stretch hip flexors, trunk flexors & shoulder extensors which will enhance their contractions SO WHERE ARE WE Muscles provide force - to move levers - about axes Which is the basis of all gymnastic skills. Muscular function forms the basis of all these Physical Qualities: - Strength - Power (speed strength) - Flexibility - Muscular Endurance Muscle force (Strength) can be enhanced by increasing muscle size. Muscle force can also be enhanced by increasing the neural drive. FIG 1 PHYSIOLOGY 1 RECAP We can increase the force of contraction, by increasing the neural drive to the muscle… INCREASE FIRING FREQUENCY - As the frequency of impulses increases, the contraction force “summates” to a higher level. - Frequency rate increases with high force & high-speed training. RECRUIT MORE MOTOR UNITS - As the number of motor units recruited for a contraction increases, so does the force of the contraction (strength). - Motor unit activation increases with high force & high-speed training. - More fast twitch motor units (as opposed to slow twitch units) are recruited when you train at high force & at high speed. SYNCHRONIZE THE FIRING OF MOTOR UNITS - As a muscle contracts, hundreds of thousands of motor units are fired in thousands of “waves”. - If all the motor units were fired at the same time, the force could break bones, thus the “waves”. - Synchronization increases with high force & high-speed training. REDUCE INHIBITORY FIRING - There are several built-in inhibitory mechanisms that reduce the force of muscle contraction (some to protect muscle from damaging itself & tendons). - Inhibitory firing is reduced by high force & high-speed training. INTER & INTRA MUSCULAR COORDINATION - Skills require movements about several joints, using several muscle groups. - Muscle force in a complex pattern can be improved simply by developing coordination of the groups of muscles so they fire optimally - this requires learning the skill & becoming efficient, which means learning the skill unloaded (with spotter, or other aid). FIG 1 PHYSIOLOGY 2 TABLE OF CONTENTS - Flexibility - Types of stretching - Energy metabolism, related to different performance - Training the energy systems FLEXIBILITY WHY ITS IMPORTANT The rubber band theory applies to each of us we will be no good until stretched Gymnastics skills often involve a variety of movements like stretches and bend that are beyond the average range of untrained athletes motion Stretching to promote flexibility, such as practicing the splits or back bends, will allow your body to maintain a limber state throughout your gymnastics training. Exercises that stretch your muscles and strengthen them allows your body to become familiar with the complex movements that will be in the correct alignment and form. Back, shoulder, and hip muscle and joint flexibility are the most frequently exercised areas during gymnastics as gymnasts split, bend, reach, and flip during routines. Gymnasts can practice developing their back, shoulder, and hip flexibility through simple exercises which gymnasts can manipulate to focus on developing specific areas of flexibility. FLEXABILLITY TERMINOLOGY Flexibility is an essential fitness component in both our functional life, as well as when we engage in physical activity. It is important that we stretch to increase the ability to temporarily elongate the tissue. The more range of motion we have, the more our joints can move without injury. Stretching will help to minimize muscle soreness and stimulate blood flow; it is also a great stress reliever. FIG 1 PHYSIOLOGY 2 TYPES OF STRETCHING ACTIVE VS PASSIVE ROM ACTIVE ROM – Internal forces are applied = you are moving your body (the motion of a joint that may be achieved by active muscle contraction) PASSIVE ROM – external forces are applied = somethings else is moving a joint for you (muscles or other parts of your body; partner or stretching machine or apparatus pr gravity provides force for the stretch) STATIC VS DYNAMIC METHODS STATIC — slowly move muscle to stretching point, then hold. Low force and long duration (usually 30 sec) DYNAMIC — continuous, slow controlled up to rapid controlled movement through the available ROM - Pre-contraction stretching (contract – relax – stretch) - Triggers the inverse myotatic reflex - Involves passive movement & active muscle action - Multiple techniques exist - Involves contraction of the muscle, followed by stretch (up to 30 s) - The benefits of stretching seem to be individual - To increase ROM all types of stretching are effective - Although PNF-type stretching may be more effective for immediate gains FIG 1 PHYSIOLOGY 2 DIFFERENT TYPES OF TTRETCHING - Dynamic - Pre-contraction - Static active - Static passive Safest gymnastics technique is active static stretching with an occasional passive assist. Pre-contraction techniques - Capable of producing dramatic increase in ROM - Limitation – partner is required Maintaining flexibility - Can decrease considerable after only 2 weeks WHAT LIMITS ROM - Joint structures (bones, ligament, cartilage) - Connective tissue (tendon, ligament, fascia) - Muscle tissue - Neural reflex activity (stretch reflex) - Individual condition of the athlete (age, sex, psychical condition, health condition, fatigue) - External conditions (temperature of the surroundings, time of the day, the quality of stretching) STRETCH REFLEX STRETCH REFLEX – is the basic function of nervous system it maintains muscle stretching and reacts to sudden, unexpected muscle stretch. This reflex is a protection from injuries caused by dangerous muscle stretching A TYPICAL EXAMPLE OF THIS IS PATELLAR FELEX - If patella is knocked on, muscle spindles, which are parallel to muscle fibres, are stretched, which results in stimulation of neural receptors. The consequence of this is neural impulse into quadriceps femoris which shortens. However, this reflex presents a problem for targeted stretching. Cease of stretch reflex presents a necessary precondition for stretching the muscle FIG 1 PHYSIOLOGY 2 EXAMPLE TISSURE RESPONSES TO STRETCHING JOINT STRUCTURE - For the most part, flexible joint are healthy joints but - Cartilaginous labrum can be damaged in excessive ranges such as hip flexion and shoulder extension CONNECTIVE TISSUE – (TENDON, LIGAMENT) - Tissue has wave-like molecular structure with slight elastic response - Improvements in ROM as a result of stretching are primary due to connective tissue adaptations - Tissue will ‘creep’ or elongate when regularly stretched – plastic response - Tissue resist fast stretches more than slow stretches (strain rate dependency) - Tissue responds to vibratory stretches - Collagen protein (main component) has increased molecular cross bridging as it ages - Thus, young tissue has inherently greater elasticity than older tissue - Regularly stretched connective tissue will hypertrophy (stretch hypertrophy) FIG 1 PHYSIOLOGY 2 MUSCLE TISSUE - The body desires that muscle tissue has an optimal overlap of actin and myosin in the resting state - If we stretch muscle tissue and disturb this state (stress), then the muscle adapts by adding sarcomeres, thus making the fibre longer, this reducing the stress by bringing the actin and myosin overlap back to optimal - The lengthening of muscle tissue in response to stretching is the same process as ‘growth’ - That is, when bones grow in length, the muscles are stretched, and in responses to this stretch, sarcomeres are added and the muscle becomes longer - Can you see that stretching connective tissue and muscle tissue will mainly increase the passive ROM - In order to increase active ROM, you must also increase the strength to the muscles that move the limb NEURAL RESPONE TO STRETCHING - Fast stretching = reflexive muscle contractions and therefore, affects the range of motion - Fast stretching also makes tissues vulnerable to injury, but the nature of gymnastics demands fast limb movements near end ranges of movement - Therefore we must use controlled dynamic stretching HOW FLEXIBLE SHOULD GYMNAST BE - Active ROM must be trained by combining stretching with strength (power) training - Passive ROM shows that tissues are elongated REMEMBER - Poor active ROM indicates strength of muscles moving limb has not occurred FIG 1 PHYSIOLOGY 2 OVER STRETCHING - By training for active ROM (strength and stretch) - We can achieve dynamic flexibility without over stretching the joints as shown - Be careful with all hyper flexibility exercises especially active ones keep your attention on the safety health and well being of gymnasts QUESTION – is passive stretching a goof way to warm up for dynamic activity? (are you warming up to stretch OR are you stretching to warm up) ANSWER – NO EXAMPLES OF WARM UP STRETCHES SHOULDERS - Table top extensions - Floor chest stretch - Cross body stretch - Stick stretch HIPS - Leg Lowers - Eccentric Split Sliders - Band Kicks - Front & Back Leg Lifts - Leg Drivers SPINE - Thoracic spine motion - Upper body control - Side lying rotation FIG 1 PHYSIOLOGY 2 RECAP WARM UP STATIC STRETCHES - Quads, hamstrings, calves, torso, shoulders) followed by dynamic stretches (arm circles, leg swings etc DYNAMIC STRETCHES - series of multi-plane dynamic stretches through full ranges of motion always with control and technique. - Emphasize working from easier single planes to more complex or multi- plane movements. ROM DEVELOPMENT - Pre-contraction techniques (Capable of producing dramatic increases in ROM) - Safest technique is active static stretching, with an occasional passive assist. - Different demands require different types and technique - Its crucial that proper methods are used to reduce joint stress and bias the stretching of soft tissue structures especially in hypermobile athletes - Avoid excessive strain being placed on the passive structures of gymnasts - Working in a complex type format is the most beneficial approach I have found that it not only can yield quick changes in flex but it can also make longer lasting changes that show up in gymnastics skills FIG 1 PHYSIOLOGY 2 ENERGY METABOLISM, RELATED TO DIFFERENT PERFORMANCE - Terms and Definitions - Production of Energy - Energy Systems & Performance - Training the Systems - Fatigue & Recovery THE HUMAN BODY IS MADE TO MOVE IN MANY WAYS - Quick and powerful - Graceful & coordinated - Sustained for many hours - And is dependent upon the capacity to produce energy. THERE IS A GREAT AMOUNT OF DIVERSITY - Quick movements-lasts a few seconds - Reduced speed-lasts for several minutes - Reduced intensity (50%) - lasts for several hours - The body uses different energy systems for each activity. \ FIG 1 PHYSIOLOGY 2 TERMS AND DEFINITIONS - Biological work - Metabolism – how a cell gets energy and removes waste = anabolism (building up) + catabolism (breaking down) - Basal metabolic rate - Human energy - Adenosine tri phosphate (ATP) - Creatine phosphate stored in each muscle cell for metabolic purposes - Aerobic - Anaerobic lactic - Anaerobic alactic FOODS AND THEIR CONVERSION TO ENERGY Cells in the body need energy to function FOOD = ENERGY Food is taken into the body as chemical energy and converted into mechanical energy in the form of muscular contractions and movements Carbohydrates, fats and proteins are the only sources of food energy and fuel PRODUCTION OF ENERGY 2 energy producing systems - Aerobic - Anaerobic lactic 1 energy storage system - Anaerobic alactic (ATP-CP) FIG 1 PHYSIOLOGY 2 ENERGY SYSTEMS AND PERFORMANCE ANAEROBIC ALACTIC ENERGY SYSYEM The storage of ATP and CP in each cell to be used for immediate biologic work No oxygen is needed (hence anaerobic) ATP-CP is used by cells for all biologic work ATP-CP is stored in limited quantity in the cell Up to 10-15 of all – out muscle effort in storage FIG 1 PHYSIOLOGY 2 EXAMPLES EXPLOSIVE POWER - Explosive bursts (or release) of energy are used in many apparatus in gymnastics this is when gymnast will use their body’s anaerobic alactic energy system (ATP-PC) to quickly produce rapid surges of power they need to perform their skills - Eg vault where the gymnast sprints down a runway to spring off a board and flip several times in the air before landing - Jumps and leaps in rhythmic and aerobic gymnastics - Combination of the explosive power difficulty elements ANAEROBIC LACTIC ENERGY SYSTEM A true energy producing system Sugar (glucose) is broken down by enzymes within each muscle cell without oxygen being needed (hence anaerobic) ATP is produced quickly and in large amounts incomplete breakdown if glucose in the absence of oxygen results in the production of lactic acid (hence the name lactic) Lactic acid causes ‘fatigue’ Lactic acid is removed from the body slowly FIG 1 PHYSIOLOGY 2 Specific anaerobic endurance is another essential asset for gymnast so that they may produce maximal performance and energy throughout the duration of their routines This is when a gymnast will use his/her body's anaerobic lactic energy system (glycolysis) which will produce quick surges of power for up to 70 seconds. Combination of energy systems allows gymnasts to perform well throughout a longer routine. EXAMPLES This is especially highlighted on the Floor exercises (WAG, MAG): Gymnasts are expected to make several fast and intricate tumbling passes across the floor - often up to five in a routine - in a strict 90 second time frame. RG: individual & group AER: all categories Several combinations of skills that require the explosive energy from ATP-PC, and the endurance from glycolysis. This is especially highlighted on the Floor exercises (WAG, MAG): Gymnasts are expected to make several fast and intricate tumbling passes across the floor - often up to five in a routine - in a strict 90 second time frame. RG: individual & group AER: all categories Several combinations of skills that require the explosive energy from ATP-PC, and the endurance from glycolysis. FIG 1 PHYSIOLOGY 2 AEROBIC ENERGY SYSEM Production of ATP from the interaction of energy substrates (CHO, FAT, PROTEIN) in the presence of oxygen Occurs in each cell Does not produce fatigue (CO2 and H2O) Long duration, moderate to low intensity large muscle activity Activity of 2 mins or longer THE BENEFITS OF AEROBIC TRAINING - Increase CAPACITY to work for long periods of time. - Improves ability to RESIST FATIGUE. - Improves ability to work at HIGH RATES for short periods. - Improves ability to RECOVER QUICKLY from intense work. - Improves ability to EXPEND HIGH AMOUNTS OF ENERGY. - Important also in gymnastics TO ENDURE LENGTHY TRAININGS we need the aerobic energy systems. FIG 1 PHYSIOLOGY 2 EXAMPLES Do we need Aerobic Energy System in gymnastics? - Gymnasts could train their body's anaerobic lactic energy system by building up their aerobic base through cardiorespiratory activity (running, etc.) - A gymnast could follow the F.I.T.T. principle (Frequency, Intensity, Time, Type) to use repetition of exercise between 10 seconds to 2 minutes. - Light (moderate) aerobic activity such as jogging or walking can also help to reduce the effect of lactic acid that is produced during glycolysis. - Gymnasts need to develop this system to increase their anaerobic threshold so they can prolong their performance without the effect of lactic acid on the body. CONTRIBUTION OF THE ENERGY SYSTEM Relative contribution of anaerobic and aerobic energy systems in maximal exercise of different durations FIG 1 PHYSIOLOGY 2 The type of energy system used and the interplay between them depend on, mostly - Frequency of the activity - Duration of the activity - Intensity of the activity - Fitness level of the activity ATP is used in all 3 energy systems FIG 1 PHYSIOLOGY 2 STRENGTH AND NEURAL ENERGY SYSTEM CONTRIBUTION FOR GYMNATICS FACTORS - Intensity of Elements. - Repetition/Duration of Intense Elements. - Total number of intense efforts. - Duration of entire effort. - Others? CONSIDERATIONS FOR THE COACH - Consider age and stage of development. - Consider specific physical conditioning. - Consider Routine construction. WHAT EFFECTS ENERGY CAPACITY - Diet (Glycogen stores, Metabolic State) - Training - Type of training, Altitude - Sex - Supplements / Drugs - GENETICS FIG 1 PHYSIOLOGY 2 TRAINING THE SYSTEMS Single training sessions - How to train each system effectively (individualization, overload) Sequencing the sessions - Progression training Periodization - When to train each system and how to avoid detraining - Peaking and tapering TRAINING TERMS EXERSISE - amount of time at the exercise effort. PAUSE - the amount of time between repetitions. INTENSITY - the percentage of maximal effort. REPETITION - a single effort or series of efforts. SET - a number of repetitions. REST - amount of time between sets of repetitions. RECOVERY - The time between training sessions. TRAINING – AEROBIC SYSTEM Frequency of Training - Minimum/Optimum/Maximum Intensity of Training - Heart Rate/ Respiration Rate/ Blood Lactate Concentration Time (Duration) of Training - Number of minutes Type (Mode) of Training - Running FIG 1 PHYSIOLOGY 2 TRAINING - ANAEROBIC LACTIC SYSTEM Type of Training - Sport Specific When to train - Pre- Season/In-season - After “Aerobic-base” has been established. Overload - Intensity…at or near performance (85% plus) - Repetition Length -20 sec to 2 min. - Set Volume - max of 4 minutes - E:P ratio 1:3 or HIIT (example: TABATA) - Rest 10-15 minutes FIG 1 PSYCHOLOGY 1 TABLE OF CONTENTS - Motivation - Causal attributions - Goals SPORT PSYCHOLOGY MEANS It is a discipline that uses psychological knowledge and skills to address - Optimal performance and well-being of athletes - Developmental and social aspects of sports participation - Issues related to sports settings and organizations DIMENSIONS OF SPORT PSYCHOLOGY FIG 1 PSYCHOLOGY 1 IMPORTANCE OF PSYCHOLOGY IN GYMANSTICS Gymnastics involves the use of a s structured progression system that benefits from the use of goals to maximize the success experiences at various levels Athletes frequently need psychological skills to cope with the various emotional demands of training and competing. High-level competition may underline symptoms associated with mental health, such as: - Eating disorders - Stress, - Anxiety MOTIVATION MOTIVATION – the tendency for the direction and selectivity of behaviour to be controlled by its consequences and for behaviour to persist until a goal is achieved INTERACTIVE SOURCES - A combination of personal and situational sources SITUATIONAL-CENTERED SOURCES - Situations or environments that has either increased or decreased the motivation level PERSON-CENTERED SOURSES - Dispositions that reflect orientations, personality traits and needs MOTIVATION THEORIES Coaches need to advise athletes what they consider the most important element to learn, practice, and compete. Solicit input from your gymnasts as to what they prioritize. Sometimes motivated behaviour is a reaction to undesirable consequences (e.g. avoiding feeling embarrassed). Theories that explain sports involvement are: - Achievement Motivation - Competence Motivation - Cognitive Evaluation FIG 1 PSYCHOLOGY 1 ACHIEVMENT MOTIVATION THEORY Gymnasts with a high need to achieve “tend to maintain a fervent and optimistic belief that success is possible” and prefer challenging tasks rather than easy activities. An outcome might be interpreted as a failure if it is perceived because of poor effort or lack of talent. COMPETENCE MOTIVATION THEORY Individuals are motivated by, and attempt to exhibit, skill mastery in achievement situations. Athletes high in perceptions of competence and self-control “will exert more effort, persist longer at tasks in achievement situations, and experience more positive feelings.” The ability can be improved in two ways - Outperforming oneself over time, - Outperforming others EXTRINSIC MOTIVATION Tendency to engage in sports to gain external rewards such as fame, praise, titles, etc. The rewards can be tangible(trophies) or intangible (public acclaim). Excessive rewards can decrease intrinsic motivation. INTRINSIC MOTIVATION Tendency to engage in sports to gain internal rewards such as enjoyment, meaning, and personal progress. Athletes want control over themselves and expect to determine what they pursue INPROVING INTRINSIC MOTIVATION - Give athletes a role in goal setting and decision making - Praise performance, not personality or character - Facilitate perceptions of competence - Use variable, not constant, positive reinforcement - Vary content and sequence of practice drills FIG 1 PSYCHOLOGY 1 HOW NOT TO MOTIVATE GYMNAST FEAR - fiery speeches, threats, harsh criticism, and insults invoke over-anxiety rather than optimal arousal and motivation. PUNISHMENT - physical exercise as punishment (push-ups, sprints, jogging) contributes to a life-long sedentary lifestyle. PRE-MEET PEP TALKS - the purpose and content is of less importance than the emotional tone and arousal level elicited by the message. PREFERENCES - showing favouritism among the team harms the interactions between gymnasts and the training environment. ASSUMING CONTENTMENT - unhappy gymnasts can be consumed by their own unpleasant thoughts but never let it show. CAUSAL ATTRIBUTIONS Causal attributions are beliefs regarding causes of events The causes to which athletes attribute their successes and failures differ depending on their cultural background The ways in which gymnast explain the causes of their performances generate positive or negative emotions COMMON CAUSAL ATTRIBUTIONS ABILITY - I was not mentally ready for this competition - I have been landing all my elements quite well lately EFFORT - I was not aggressive enough in todays training - I gave it my best even if I did not qualify for finals TASK DIFFICULTY - Injuries have really hurt me - The other gymnast timing was excellent LUCK - I cannot seem to get ant breaks - The judges killed us on this competition FIG 1 PSYCHOLOGY 1 CAUSAL EXPLANATIONS in 1979, Weiner suggested that we perceive and explain success and failure in terms of 4 categories WEINERS REFORMULATED MODEL Locus of control in the degree to which one believes to have control over the outcome of events or not This concept was developed by rotter in 1954 but remains central to determine if an athlete believes that a particular result in sport is due to internal or external factors Ability and effort are internal factors Task difficulty and luck are external ones In 1985 the causal attribution model evolved to include three dimensions - Causality - Stability - Control The two factors in the UNSTABLE dimension are EFFORT and LUCK. Making low-ability attributes can be devastating to a gymnast’s long-term commitment to the sport, but attributing all results to luck can also be prejudicial. Stability reflects changes in the athlete’s attributions over time or from situation to situation. The two factors in the STABLE dimension are: ABILITY and TASK DIFFICULTY which can be consistent and predictable. FIG 1 PSYCHOLOGY 1 CHANGING LOCUS OF CAUSALITY Can certain experiences lead to shifting control from external to internal or vice versa? Shifting to an external locus can be desirable to engage in less self-blame after failure. Shifting to an internal locus can be desirable when an athlete takes responsibility and decides to train more consciously. DATAT SHOWS Athletes from Men’s Artistic Gymnastics were more likely to have their success credited to sport skill/strength, and their failure attributed to a lack of concentration and a lack of athletic ability compared to the aggregate of other male Olympians. Male gymnasts were also more likely to receive comments about being modest or introverted. HOW TO INCREASE MOTIVATION WITH CASUAL ATTRIBUTION - Avoid saying that errors are caused by poor ability. - Indicate that task difficulty can explain a medal result. - Determine if a gymnast has superstitious rituals done to attract good luck to a performance. - Analyse each competition performance a week after, to listen to the attributions your athletes believe in. GOALS It is an / a - Objective - Measure of outcome - A standard - Aim of action - Level of proficiency - Idea of the future - Desired result Goals play a huge part in achieving optimal performance FIG 1 PSYCHOLOGY 1 Setting goals help understand where performance is currently at and where improvement is needed SMART GOALS SMART goals for athletes SPECIFIC - what objective needs to be accomplished - what steps will you take to achieve it MEASUREABLE - can you quantify your goal - how will you track your progress ACHIEVABLE - is your goal within reach - what limitations might impede your goal RELEVANT - what is the benefit attached to your goal - why does it matter to you TIME-BOUND - what is your goals deadline - do you have a particular date to achieve it THE EMPIRICAL DATA SHOWS Specific difficult and challenging goals lead to higher levels of task performance than easy goals, no goals or vague ‘do your best’ goals There is a relationship between performance and degree of goal difficulty The only exception is when subjects reach the limits of their ability at high goal difficulty levels FIG 1 PSYCHOLOGY 1 PRINCIPLES OF GOAL SETTING What are the principles of goal setting? Choose SMART goals - Set moderately difficult but realistic goals. - Plan goal-achievement strategies. - Develop performance and process goals. - Search for goal support. - Consider the level of motivation. - Foster commitment towards the goals. - Provide evaluation and feedback for each goal. - Record the goals and write them down. - Prioritize goals for the month and the year. FIG 1 PSYCHOLOGY 2 TABLE OF CONTENTS - Reinforcement - Emotions - Imagery REINFORCEMENT The use of rewards and punishments that increase or decrease the likelihood of a similar responses occurring in the future REINFORCEMENT EXAMPLES EFFECTIVE REINFORCEMENT Match the 2 basic premises for an effective reinforcement with the consequence they both will create ACTION WITH A PLEASANT CONSEWUENCE – people will trend to try to repeat the behaviour to receive an additional positive consequence ACTION WITH AN UNPLEASANT CONSEQUENCE – people will tend to try to not repeat the behaviour so they can avoid more negative consequences FIG 1 PSYCHOLOGY 2 PRINCIPLES OF REINFORCEMENT ARE COMPLEX - The same reinforcer will affect 2 people differently - People cannot always repeat the reinforced behaviour - People may have multiple (perhaps opposing) reinforcements available GUIDELINE FOR USING POSITIVE REINFORCEMENTS Choose efficient reinforcements and always ask your athletes what they prefers ACTIVITY REINFORCERS - Getting a rest - Playing a different position - Playing a game rather than drilling - Taking a trip to play another team MATERIAL REINFORCERS - Medals - Ribbons - T-shirt - Trophies SOCIAL REINFORCERS - Pat on the back - Praise - Publicity - smile SPECIAL OUTINGS - going to a professional game - hearing a presentation from a professional athlete - throwing a team party FIG 1 PSYCHOLOGY 2 POSITIVITY REINFORCEMENT WHAT SHOULD BE REINFORCED - Reward appropriate behaviours - Reward effort - Reward emotional and social skills - Reward performance not only outcome - Reward successful approximations - Provide performance feedback EXAMPLES OF REINFORCEMENT Coaches can use public reward boards that show the achievements of each gymnast after every week. These achievements can be on different levels - Athletic skills - Effort - Helping teammates - Creating a good training atmosphere For children, little sticky stars or smileys can be used For teenagers, specific rewards based on their own preferences can be written on the board (e.g. Laura deserves to select a team activity for the weekend) GUIDELINES FOR USING POSITIVE REINFORCEMENT FIG 1 PSYCHOLOGY 2 GUIDELINES FOR USING PUNISHMENT NEVER USE THE FOLLOWING PUNISHMENTS EARLY STAGE OF LEARNING – continuous and immediate reinforcement LATER STAGES OF LEARNING – use of intermittent, immediate reinforcements FIG 1 PSYCHOLOGY 2 WHAT IS EMOTION An emotion is normally quite short-lived, but intense and it is likely to have a definite and identifiable cause, like being happy after winning a competition But it is not a mood EMOTIONS EXAMPLES FIG 1 PSYCHOLOGY 2 KEY ELEMEMTS OF EMOTIONS (TENENBAUM AND EKLUND) - Subjective experience - Physiological response - Behavioural response Click below to check basic emotions categorized by its valence (Lazarus, 1991) CIRCUMPLEX MODEL OF EMOTION (RUSSELL 1980) Emotions can be distributed on 2 dimensions - Arousal / intensity – how intense are the experienced emotion - Valence – are the emotions experienced more positive or negative FIG 1 PSYCHOLOGY 2 CHECKLIST OF PERFORMANCE STATES (WEINBERG AND GOULD) A gymnast should - Increase their awareness of their emotions - Check whether the emotions are positive or negative - Check whether they are more or less intense Thoughts and feeling can only be controlled if one is aware of ones psychological states What to do with the increased awareness of my emotions - Channel it in ways that will be beneficial to their performance - Develop strategies to replace them with healthy alternatives - Gymnast should use this to their advantage - Recognize when their emotions are not helping them - Learn to live and express their emotions in positive ways IMAGERY WHAT IS IMAGERY It is the process of creating or re-creating an experience in the mind which has two steps - Recalling pieces of information from memory, stored from experience. - Shaping the pieces into meaningful images. FIG 1 PSYCHOLOGY 2 IMAGERY EXAMPLES EFFECTIVNESS AND EFFECTS OF IMAGERY Most important aspects for effective imagery are - controllability and vividness. You need to choose a comfortable perspective, (re)create the emotional feeling associated with the task or skill you are trying to perform and use as many senses as possible. Careful monitoring in the following effects of imagery - Creating anxiety - Directing attention to irrelevant factors - No control - imaging failure or mistakes - Overconfidence FIG 1 PSYCHOLOGY 2 FUNCTIONS AND USES OF IMAGERY TRAINING PROGRAMS CALLED PETTLEP (HOMES AND COLLINS)I IMAGERY RESEARCH - Effectiveness across of range of skills and abilities. - Practitioners consider a range of factors when implementing imagery – intervention duration, skill type, delivery format, and combining imagery and physical practice. - Use of imagery at different locations – before/during/after practice and competition.