Task B: The Muscular System

PASS MERIT DISTINCTIONP3: IDENTIFY the LOCATION of the MAJOR MUSCLES in the human bodyP4: DESCRIBE the FUNCTION of the MUSCULAR SYSTEM and the different FIBRE TYPES

M1: EXPLAIN the FUNCTION of the MUSCULAR SYSTEM and the different FIBRE TYPES

D1: ANALYSE the FUNCTION of the MUSCULAR SYSTEM and the different FIBRE TYPES

VERB PLAIN ENGLISHDescribe Try to “Paint a picture” in words. Assume that the person that you

are Describing to does not know anything about the subject that you are describing. Tell them what you have learned.

Identify Create a List of KEY FEATURES.(e.g) Steven Gerrards Strengths are: Aerobic Endurance, Goal scoring ratio etc….

Explain Once you have Described the subject, often you will need to give further details and reasons why. (e.g) Once you have described England’s poor performance in the World Cup, you may also give some reasons why the players did not perform as well as they could.

Analyse You need to SELECT the KEY POINTS and EXPLAIN each point providing REASONS for each point and also looking at POTENTIALIMPACTS.(e.g.) If you were looking at the performance of Barcelona you may pick out the key points in their success – Money, Lionel Messi, Iniesta etc.. You would then explain the contribution of each player and also look at what the club could do to regain the Champions league next season

Vastus Intermedius

Types of Muscle

• Skeletal

• Smooth

• Cardiac

Skeletal Muscle• Also called Stripy/striated muscle

• Voluntary – Under Conscious control

• Over 700 skeletal muscles in the body

• Attached to bones

• Is made up of different muscle fibres

Smooth Muscle• Involuntary – Works without thought

• Found in the walls of hollow internal structures such as blood vessels, the stomach, intestines, urinary bladder

• A smooth muscle is non-striated (smooth)

• Peristaltic Action – Contract consecutively, one after the other

Cardiac Muscle• Found in the walls of the heart

• Its contraction is involuntary (not under conscious control)

• Pumps blood around the body, without getting tired

• It is striated (has light and dark bands)

Muscle Function• Muscles cross joints that they move

• Pulling force from muscles causes movement

• Muscle Tone – State of readiness to work

• Strength of contraction – Depends on the number of fibres that have been recruited

Function of the Muscular System• Antagonistic Muscle Pairs

• Muscles work together in groups to create movement

• Muscles can function as the following: Agonist, Antagonist, Synergist, Fixator.

Agonist

• Shortens to move a joint

• Also called the PRIME MOVER

Antagonist

• Relaxes when the agonist muscle is working

• Has a BRAKING effect

Synergist / Fixator

• Synergist = Muscles that help the agonist muscle

• Fixator = Stop unwanted movement

• Stabilise the movement

Types of Muscle Contraction

• Isometric

• Concentric

• Eccentric

• Isokinetic

Isometric

• Muscle tenses

• Stays the same length

• Joint angle stays the same

• E.G. Holding a Press-up

Concentric

• Muscle shortens under tension

• Origin and Insertion move closer together

Eccentric

• Muscle lengthens under tension

• Origin and Insertion move further apart

• E.G. Bicep Curl – Lowering Phase

Isokinetic

• Muscle contracts at a CONSTANT SPEED

• Need specialised equipment that controls the muscle action

Muscle Fibre Types

• There are three types of muscle fibre:

• Type 1

• Type 2a

• Type 2b

Type 1 Slow Twitch Fibres

• Contract slowly

• Lots of blood vessels

• Low Force

• Fatigue resistant

• Low Intensity, Long duration activities

Type 2a Fast Oxidative Glycolytic Fibres• Type of Fast Twitch Fibres

• Fast Contractions

• Produce Force

• Resistant to Fatigue

• E.G. Middle Distance Runners

Type 2b Fast Glycolytic Fibres• Type of Fast Twitch Fibres

• Fast Contractions

• Lots of Force

• Fatigue quickly

• Anaerobic Activities

• E.G. 100M