The Muscular System Im only 80 yrs Young
- Slides: 20
The Muscular System I’m only 80 yrs. Young!
Function of Muscles Produce movement Maintain posture Stabilize joints Generate heat
The Muscular System Muscles are responsible for all types of body movement Three basic muscle types are found in the body –Skeletal muscle –Cardiac muscle –Smooth muscle
Skeletal Muscle Characteristics Most are attached by tendons to bones
Skeletal Muscle Characteristics Striated – have visible banding Voluntary – subject to conscious control Cells are surrounded and bundled by connective tissue
Smooth Muscle Characteristics Has no striations Spindle-shaped cells Single nucleus Involuntary – no conscious control Found mainly in the walls of hollow organs
Cardiac Muscle Characteristics Has striations Usually has a single nucleus Joined to another muscle cell at an intercalated disc Involuntary Found only in the heart
Muscles and Body Movements Movement is attained due to a muscle moving an attached bone
Muscles and Body Movements Muscles are attached to at least two points – Origin – attachment to an immovable bone – Insertion –attachment to a moveable bone
Five Golden Rules of Gross Muscle Activity 1. All muscles cross at least one joint 2. The bulk of muscles lies proximal to the joint crossed 3. All muscles have at least 2 attachments: origin & insertion 4. Muscles only pull. They never push 5. During contraction, the muscle insertion moves toward the origin
Effects of Exercise on Muscle Aerobics result in stronger muscles due to increase blood supply Muscle fibers increase mitochondria and oxygen storage Muscle becomes more fatigue resistant Heart enlarges to pump more blood to body Does not increase skeletal muscle size
Effects of Exercise on Muscle Resistance training results in the increase of muscle size & strength Individual muscle cells make more contractile filaments & connective tissue increases
Body Movements
Body Movements
Trunk Muscles
Deep Trunk and Arm Muscles
Muscles of the Pelvis, Hip, and Thigh
Muscles of the Lower Leg
Superficial Muscles: Anterior
Superficial Muscles: Posterior
