CHAPTER THREE Physical Changes

Why Do We Age?—Biological Theories Rate-of-Living Theories Limited energy to expend in a lifetime Excess calories may reduce lifespan

Cellular Theories Limited number of times a cell can divide (Hayflick limit) –Telomeres (tips of chromosomes) become shorter with each cell division Cross-linking –Tissue becomes stiffer with age Free radicals –Reactive chemicals cause cellular damage

Programmed Cell Death Theories Aging may be programmed into genetic code –Cells may be pre-programmed to self- destruct

Changes in Skin –Why does our skin wrinkle? Four-step process –Outer layer becomes thinner because of cell loss –Collagen fibers lose flexibility –Elastin fibers lose ability to keep skin stretched out –Underlying fat layer diminishes –Environmental factors affecting skin Sun exposure Smoking –Other skin changes Pigment-containing cells decrease Age spots, moles Varicose veins Changes in the body that occur with age

Changes in the Hair –Hair loss caused by destruction of germ centers that produce hair follicles –Graying caused by cessation of pigment production –Other hair changes Males do not lose facial hair. Females gain facial hair. –Caused by hormonal changes Changes in the body that occur with age

Attributes of the aging voice: –Lowering in pitch –Increased breathlessness and trembling –Slower and less pronounced pronunciation –Decreased volume May be due to normative changes or poor health Changes in the body that occur with age

Decrease in height with age –Between mid-50s and mid-70s men lose about 1 inch and women 2 inches –Compression of the spine –Changes in posture Weight gain then loss –Usually a weight gain between 20 and 50 –Usually a weight loss throughout the older years –How different between men and women? Research suggests that one lives longer with a normal body weight Changes in Body Build

Muscles –Strength loss: age 70, up to 20%; age 80, up to 40% –No difference in the rate of muscle change between men and women Changes in Mobility

Bones –Loss begins in the late 30s, accelerates in the 50s, and slows in the 70s –Osteoporosis: loss of bone mass; leading cause of broken bones in older women

Changes in Mobility Joints –Osteoarthritis occurs when the bones beneath cartilage become damaged –Rheumatoid arthritis is a disease of the joints

Changes in Vision Structural changes in the eye –Decreased ability to allow light into the eye –Adaptation between light and dark is slower –Presbyopia: difficulty focusing on close objects –Cataracts: spots develop on the lens, clouding vision –Glaucoma: pressure in the eye may result in loss of peripheral vision

Changes in Vision Retinal Changes –Macular degeneration: loss of receptor cells in the eye –Diabetic retinopathy: may result in blindness

Changes in Hearing Due to normative age-related changes Due to loud environment –Presbycusis: Reduced sensitivity to high- pitched tones Hearing Loss Simulation - YouTube Hearing Loss Simulation - YouTube

With age there is a loss of touch only on smooth skin of the hand Temperature regulation is sometimes more difficult in older adults Changes in Somesthesia

Kinesthesis is ones sense of where they are in space; involving muscles and joints Vestibular system is in the inner ear and helps with balance and movement –Fear of falling, dizziness, vertigo increase with age Environmental hazards –Loose rugs –Slippery floors –Hip protection Tai Chi— –Helps maintain banlance Changes in Balance

Taste receptor cells do not change in quantity across the lifespan Taste is dependent on smell Smell diminishes after age 60 and sometimes can be used to diagnose Alzheimer’s disease Changes in Smell and Taste

Underlying cause of diminished capacity –Accumulation of fat deposits –Stiffening of the heart muscle Changes in the Cardiovascular System

Congestive heart failure: cardiac output declines, heart gets larger—most common cause of hospitalization for those over 65 Angina pectoris: chest pain due to insufficient oxygen supply to heart Myocardial infarction (MI): blood supply is severely reduced; pain may or may not be present Cardiovascular Disease: #1 cause of death

Atherosclerosis: build-up of fat deposits; may lead to CVA Cerebrovascular accident (CVA) or stroke: blood flow to brain is cut off Hypertension: high blood pressure Cardiovascular Disease: #1 cause of death

Respiratory Diseases –Chronic obstructive pulmonary disease (COPD), includes: Emphysema –Destruction of membranes around the air sacs in the lungs –82% self-induced by smoking Chronic bronchitis –Bronchial passageways become irritated by dust, fumes, air pollution, etc. –More common with people over 45 Changes in the Respiratory System

Changes in the Female Reproductive System –Perimenopause Transition to menopause involving changes in reproductive organs and sexual functioning Genital organ change begins in the 40s –Menopause The point at which the ovaries cease to release eggs –Hormone Replacement Therapy (HRT) –No physiological reason why most women cannot continue sexual activity into old age. –Climacteric: the transition from reproductive to non- reproductive years

Changes in the Male Reproductive System –Unlike menopause, no event to mark male reproductive changes Gradual decline in testosterone levels Decrease in sperm production (30% between 30 and 60) –Prostate cancer a real threat –Impotence/Erectile Dysfunction: treatable with drugs such as Viagra Psychological Implications –For healthy adults, sexual activity is a lifelong option.