The muscular system is composed of muscle fibers that are of varying lengths and shapes and form muscles, making up 42% of total body weight. Muscles contract and allow for movement, maintain posture and temperature, and provide stability by holding bones together. There are three types of muscle tissue: skeletal muscle which is voluntary and attached to bones, smooth muscle which is involuntary and found in internal organs, and cardiac muscle which is striated and involuntary, found only in the heart. The development and strength of muscles changes throughout the lifespan from growth and development in children to declines in mobility and muscle properties in older adults.

1. Chapter 22 The Muscular System

2. Objectives Describe the muscular system of the body. Explain the functions of muscle. Identify the types of muscle tissue. Lifespan considerations Patient teaching

3. Introduction The muscular system is composed of specialized cells called muscle fibers. These fibers are different lengths and shapes and form to become muscles. Muscles make up about 42% of a person’s total body weight. Muscle fibers are held together by connective tissue , enclosed in “fascia”. Muscles must have proper oxygen and nutrition to function properly.

4. Functions of Muscle Contractibility . All muscles attached to bones, organs and blood vessels are responsible for movement . All movement is a result of contraction. Tonicity - posture through partial contraction of the skeletal muscle.

5. Functions of muscles con’t Heat production- produce heat through chemical changes involved in muscular activity, maintains normal body temperature. Stability - muscles are responsibly for holding bones together .

6. Types of Muscle Tissue Muscle Tissue Skeletal Voluntary Stiated cells Smooth Involuntary Blood vessels, Urinary bladder, Digestive system Cardiac Muscle Tissue Found in the Heart Striated and Involuntary

8. Lifespan Considerations The Child- from fetal development to growth through childhood, the muscles and bones continue to grow. Development is cephalocaudal and proximaldistal. Freedom and movement is needed to develop these muscles.

9. Lifespan Considerations The Adult – changes related to mobility are most obvious in the older adult. Changes in strength, endurance, ROM, coordination, elasticity and flexibility of connective tissue. Regular exercise is important.

10. Patient education Healthy attitude towards exercise Good posture Dietary supplements Lifestyle modification