UNIT 1 – ANATOMY & PHYSIOLOGY

P3 – Identify the Location of the Major Muscles in the Human Body

Introduction There are over 640 muscles in your body They have a very good blood supply to provide

oxygen & nutrients and remove waste products Your muscles are controlled by your nervous system When a message is sent to your muscles it makes

them contract When your muscles contract they get shorter & pull

on the bones that they are attached to One end doesn’t move (the origin) the other end

moves towards the origin (the insertion)

Muscle Characteristics

Contractility – the ability to shorten

Excitability – responds to stimulus

Extensibility – can be stretched (blu-tac)

Elasticity – if stretched, will return to original length (elastic band)

Types of Muscles

Cardiac Muscle

Very specialised Only found in the heart Works continuously Never gets tired Involuntary Striated/striped under a microscope Has it’s own blood supply

Smooth Muscle

Found in walls of digestive system & blood vessels

Involuntary Performs automatic tasks

Skeletal Muscle

Attached to bones Striated/striped under a microscope Voluntary Responsible for stability & movement

Muscle Location Origin Insertion Action

Biceps Anterior Upper Arm Scapula Radius Elbow Flexion

Triceps Posterior Upper Arm Humerus Ulna (olecranon)

Elbow Extension

Muscle Location Origin Insertion Action

Deltoids Top of Shoulder Clavicle & Scapula

Humerus Shoulder Abduction

Latissimus Dorsi

Middle Back Pelvis & Spine Humerus Shoulder Adduction

Muscle Location Origin Insertion Action

Pectoralis Major

Chest Sternum & Clavicle

Humerus Horizontal FlexionShoulder adduction

Teres Major

Posterior Shoulder

Scapula Humerus Shoulder AdductionInternal Rotation

Trapezius Upper Back Skull & Vertebra Scapula & Clavicle

Shoulder ElevationShoulder RetractionShoulder DepressionNeck Extension

Muscle Location Origin Insertion Action

Rectus Abdominis

Front of Stomach

Pubic bone Xiphoid Trunk flexion

Internal Obliques

Sides of stomach

Iliac crest ribs Trunk rotation

External Obliques

Sides of stomach

Ribs Iliac crest Trunk rotation

Errector Spinae

Either side of spine

Sacrum Ribs, vertebra, skull

Spine extension

Muscle Location Origin Insertion Action

Rectus Femoris

Front of hip & thigh

Pelvis Tibia Hip flexionKnee extension

Vastus Medialis

Front of thigh Femur Tibia Knee extension

Vastus Intermedialis

Front of thigh Femur Tibia Knee extension

Vastus Lateralis

Front of thigh Femur Tibia Knee extension

Muscle Location Origin Insertion Action

Gluteus Maximus Backside Pelvis Femur Hip extension

Biceps Femoris Back of thigh Pelvis (ischium)

Fibula Hip extensionKnee flexion

Semimembranosus Back of thigh Pelvis (ischium)

Tibia Hip extensionKnee flexion

Semitendinosus Back of thigh Pelvis (ischium)

Tibia Hip extensionKnee flexion

Gluteus Maximus

Muscle Location Origin Insertion Action

Tibialis Anterior Front of shin

Tibia 1st metatarsal & tarsal

Dorsiflexion & inversion

Gastrocnemius Calf Femur Calcaneum Knee FlexionPlantarflexion

Soleus Calf Tibia Calcaneum Plantarflexion