Presentation on theme: "Unit 1: The Body in Sport 2. Understanding the muscular system and how it is affected by exercise In this section you will learn how the skeletal and muscular."— Presentation transcript:
1 Unit 1: The Body in Sport2. Understanding the muscular system and how it is affected by exerciseIn this section you will learn how the skeletal and muscular systems are linked in the creation of movement during sports activities. You will also learn about the structure of joints and levers in the production of movement.
2 Classification of muscles All sports performers need to be able to move. Movement is possible through the use of muscles, but not all muscles bring about movement.There are three different types of muscle tissue that make up the muscular system.Can you name them?
3 The three different types of muscle tissue are: Cardiac muscle, which is only found in the heart.Smooth muscle, also known as involuntary muscle.Skeletal muscle, also known as voluntary muscleThe structure and function of each of these muscle tissues are very different, and they are controlled by different methods
4 Cardiac MuscleThis type of muscle is only found in the heart, and is a special form of involuntary muscle in that we have no direct conscious control over it. It also differs from voluntary muscle in that it does not tire, but continues to contract and relax throughout our lives.
5 Involuntary or Smooth Muscle Examples of this type of muscle can be found in parts of the digestive tract propelling food through the digestive system and the blood vessels that aid blood flow away from the heart to all parts of the body.
6 Skeletal or Voluntary Muscle This type of muscle is attached to the skeleton of the human body and is responsible for bringing about movement and maintaining body posture. These muscles are controlled by the central nervous system and we move these muscles with conscious thought.
7 Your body has over 600 muscles to enable it to move. You are going to concentrate on just 11. Can you name any muscles?HamstringsQuadricepsTricepsDeltoidLatissimus dorsiGastrocnemiusBicepPectoralGluteus maximus / GlutealsTrapeziusAbdominals
10 Muscle and Sporting action Triceps - Extends lower arm at the elbowVolleyball player has arms outstretched to block theballBiceps - Flexes arm at the elbowTennis serve – racket preparation, when racket isbehind headDeltoids - Abducts upper arm at the shoulderPreparation for a cartwheel in gymnasticsPectorals - Adduction of upper arm at the shoulderArm action in front crawl (pull)Trapezius - Adducts and rotate scapula, rotation ofhead at atlas and axisLifting of the head to watch the flight of the shuttlein badminton
11 Muscle and Sporting action Gluteals - Extends the leg at the hipRunning action, one leg is left stretched backbehind the otherQuadriceps - Extends the leg at the kneeFollow through after kicking a ball in footballHamstrings - Flexes the leg at the kneeTaking the leg back in preparation to strike the ballin rugbyGastrocnemius - Plantar flexion of the footGoing up onto toes prior to take off in a divingcompetitionLatissimus dorsi - Adducts and rotates thehumerus at the shoulderPulling the arm back in archeryAbdominals - Flexes and rotates the trunkForward action in sit ups
12 Structure and function of skeletal muscle Skeletal muscles aremade up of manythousands of fibres.These in turn aremade of evensmaller fibres calledmyofibrils. It iswithin these smallestfibres that thecontraction of themuscle takes place.
13 Muscle movementSkeletal muscle has a vast supply of nerve and blood vessels. Skeletal muscle is also termed voluntary muscle because movement is created via conscious thought process. Muscles pull to produce movement. In other words, the cells of the muscle tissue contract and then relax to their original size.
14 How Muscles Work: When you move a part of your body your muscles will either:CONTRACT – Bulge (get fatter) and shortenOr:RELAX – Return to their original length
15 Muscle ContractionMuscles work (contract and shorten) when stimulated (told to do so) by the central nervous system (CNS). The brain sends messages via the spinal cord to the muscles it wishes to move. The spinal cord acts like a telephone wire.Muscular tissue has the ability to contract (shorten and bulge) and then return to its original length because it has ELASTICITY.Voluntary / Skeletal muscles usually works across a joint. They are attached to both bones by strong cords called Tendons.Tendons are white, flexible, very strong and are different shapes depending upon the muscle.In other words Tendons are the cords that connect Muscles to Bone so a muscle has tendons at both ends.
16 Antagonistic PairsMuscles work in pairs to provide movement for physical activity, for example the biceps and triceps work together to create movement.
17 Antagonistic pairs Prime movers – these muscles determine the movement of an action viacontraction. For exampleduring the bicep curl, theprime mover during theflexion phase is the bicep.Antagonistic – this muscleworks together with theprime mover but creates anopposition action. Using theexample of the bicep curlagain, during the flexionphase the triceps enable thearm to bend at the elbowjoint for the bar to movetowards the shoulder girdle.
18 Antagonistic pairs During the downward phase of the bicep curl the oppositeoccurs. For example theprime mover (Agonist) is thetriceps and the antagonisticmuscle is the bicep.
19 Origins and Insertion Muscles PULL on Bones – muscles are attached to two different bones withtendons.To make a joint move – one of thesebones will move but not the otherORIGIN –attached to the STATIONARY boneINSERTION – attached to the MOVING bone
21 Muscle ContractionMuscles contract to produce movement. There are three main types of muscle contraction: two where obvious movement occurs and one where no obvious movement is visible.Isometric contraction is where the muscle stays the same length during contraction, or when the activity is being carried out. Tension occurs in the muscle but the distance between the ends stay the same
22 Muscle ContractionIsotonic concentric contraction is when the muscle shortens when performing an action. There is obvious movement when the ends of the muscle move closer together.Isotonic eccentric contraction occurs when the muscles lengthen under tension. The ends of the muscle move further away during an action.