The Muscular System

How many muscles are in the human body???? approximately 850 650 are skeletal muscles 200 make up cardiac and smooth

There are four characteristics associated with muscle tissue: Excitability Contractility Extensibility Elasticity - Tissue can receive & respond to stimulation - Tissue can shorten & thicken - Tissue can lengthen - After contracting or lengthening, tissue always wants to return to its resting state

The characteristics of muscle tissue enable it to perform some important functions, including: Movement – both voluntary & involuntary Maintaining posture Supporting soft tissues within body cavities Maintaining body temperature

Types of muscle tissue: Cardiac – myocardium of the heart (involuntary) Skeletal – attached to bone (voluntary) Smooth (Visceral) – organs/blood vessels (involuntary)

Skeletal muscle movements Flexion/extension; Abduction/adduction; Inversion/eversion Rotation – left/right; internal(medial)/external(lateral) pronation/supination; Elevation/depression Protraction/retraction; Dorsiflexion/plantar flexion

Sternocleidomastoid (neck)

Deltoid (shoulder)

Pectoralis Major (breast)

Bicep Brachii (stud muscle)

Flexors (forearm “Popeye”)

Rectus Abdominis (6 pack abs)

External Oblique (side abs)

Rectus Femoris (Quads)

Sartorius (longest muscle)

Trapezius (traps)

Latissimus Dorsi (back lats)

Tricep Brachii (tris)

Extensors (back of forearm)

Gluteus Maximus (gluts or buttocks)

Bicep Femoris (hamstrings)

Gastrocnemius (calf)

Achilles Tendon (not a muscle)

Tendon attaches from the gastrocnemius (calf) to the calcaneus bone

Achilles tendon tear