Physical Changes Adulthood (9-14-16)

I. Why do we age (again)

Rate of living theories

Gompertz law: date rates in humans double every eight years (Moody & Sasser, 2015, p. 37), a 38-year-old is twice as likely to die as a 30-year-old, a 46-year-old is four times as likely to die as a 30-year-old; rate of aging is roughly correlated with Gompertz low: rate of doubling is three months in a mouse and about 10 days in a fruit fly.

Do we only have so much energy to expend in a lifetime?

restricting activities in insects may increase their life spans

some mammals live longer if hibernation is induced

the number of calories consumed is related to longevity

age of maturity in mammals is related to longevity

But -- examination of many species does not support a direct relationship between metabolism and length of life

Cellular theories


free radical damage

wear-and-tear theories

somatic mutation theories

accumulative waste theories

autoimmune theories

Programmed-cell-death theories

aging-clock theories

replication senescence & telomeres

lower levels of the hormone dehydropiandrosterone (DHEA)

II. Physical changes is in Young Adulthood

Changes in physical appearance and declines in body functioning in the 20's and 30's tend to be gradual

organ reserve: the part of the total capacity of our body's organs that we do not normally need to use

the most significant changes in organ reserve occur in the heart, lungs, and kidneys

"A 50-year-old man might fish all day with his 25-year-old son and take a long walk with him without becoming exhausted, but has little change of winning a footrace against him." (Fiore, 2011, p. 210)


gradual changes from approximate age 30 in vision and hearing

Cardiovascular: heart disease is leading cause of death in adult population


Maximum vital capacity declines by approximately 10 percent per decade after age 25

a common measure of overall aerobic fitness is Maximum oxygen uptake (VO2 max): the ability of the body to take in and transport oxygen to various body organs. At rest VO2 shows only minimal decrements with age; when measured during exercise (like a treadmill test), it shows a decline with age of about 1% a year, beginning between ages 35 and 40 (Goldberg, Dengel, & Hagberg, 1996)

Aging of the lungs can make it harder for older adults to meet the body's need for oxygen while exercising

Immune System: declines after age 20, usually due to changes in thymus the compromise the immune response; is also weakened by psychological and physical stress

T cells are a type of white blood cell produced in the bone marrow and maturing in the thymus, attacks antigens (foreign substances in body) directly; shows most decline of immune system

B cells are a type of white blood cell produced in the bone marrow which secrete antibodies into the bloodstream to multiple, surround antigens, allowing the antigens to be destroyed by the body

Skin and hair: loss of elasticity; hair becomes thinner and may gray (lose color pigmentation)

Reproductive capacity

Women's fertility decline with age, especially in late 30's and in the 40's

Men's semen volume, sperm concentration and motility gradually decrease after age 35, contributing to reduced fertility rates in older men; risk of mutations in genetic material may increase with advancing age (increased paternal age may be a risk factor for autism)

Motor performance

Declines in heart and lung functioning during exertion, combined with graduate muscle loss, lead to changes in motor performance

In ordinary citizens, the impact of biological aging on motor skills is difficult to separate from decreases in motivation and practice

The upper biological limits of motor capacity is reached in first part of early adulthood, but biological aging accounts for only a small part of age-related decline until advanced old age

III. Middle Adulthood : physical development

Middle Adulthood: When does "middle" begin?

ages 40 to 65

midpoint, not end of life

continuations of adulthood changes

Physical Changes with Age

Vision: by the 40's, visual "accommodation" becomes more difficult for nearby objects

by the 60's, the lenses loses their capacity to adjust to objects at varying distances entirely, presbyopia ("old eyes")

color vision declines, "night vision" declines

glaucoma--poor fluid drainage leading to destructive buildup of pressure in eye--becomes the leading cause of blindness


about 14% of Americans between 45 and 64 suffer from hearing loss, often due to age-related changes called presbycusis ("old hearing")

after age 50 high frequency loses become more apparent

gender, and possibly population differences

males have earlier, more rapid loss


the skin become less elastic and supple, "age spots" appear, blood vessels in the skin become more visible

sun exposure tends to exacerbate wrinkling and spotting



young adult voices tend to be full and resonate; older adult voices tend to be thinner or weaker

age related changes show lowering of pitch, increased breathlessness, and mumbling, slower & less precise pronunciation, decrease volume

may reflect changes in larynx, respiratory system, and muscles; may reflect poor health that are not part of normal aging


both males and females tend to loss muscle mass and gain weight

basal metabolic rate slows, leading to a decreased caloric need (but not appetite)

weight bearing/resistance training exercise can help offset both excess weight and muscle loss


mineral content of bones declines, bones become more porous, and bone density declines

disk collapse in the spinal column lead to a decrease in height

great loss of bone density lead to the disorder of osteoporosis

Reproductive System

the climacteric, the mid-life transition in which fertility declines, brings an end to reproductive capacity in women and decreased fertility in men

menopause: estrogen production decreases over a decade the concludes with menopause, late 30's to late 50's--the end of menstruation and reproductive capacity

decreased genital size and sensitivity, become less easily stimulated, and the vagina lubricates more slowly during arousal

hot flashes and sexual problems are linked with menopause

common reports of less satisfying sleep, irritability, and mood problems are not clearly linked to menopause

psychological and physical effects

expectation and "meaning" dramatically affects the experience of menopause

marked cultural and subcultural differences

males experiences a decrease in quantities of semen and sperm produced after age 40, testosterone production reduces

erectile dysfunction--inability to attain/sustain an erection when desired--becomes more common in mid-life

drugs that increase blood flow to the penis and commonly prescribed for treatment

increased risk of mutation in germ cells in older males

Health and Fitness

Behavior patterns/habits markedly influence health during mid-life

Type A behavior pattern: extreme competitiveness, impatience, angry outbursts

cardiac health and survival

the research literature: method variance, individual differences, and some "real" effect

hostility as the most dangerous element

Hardiness: control, commitment, and challenge that are associated with more adaptive coping with stress

regard most experiences as controllable

display a committed, involved approach to daily activities

view change as a challenge

IV. Late Adulthood : physical development

speech comprehension in the elderly

Physical Development in late Adulthood

Life expectancy

"average life expectancy" is the number of years a person born in a particular year can expect to live

"average life expectancy" can also be defined as the age at which half of the people born in a particular year will have died

in 2008 the average life expectancy in the U.S. reached 78.1 years

declines in infant death rates have historically been a major contributor to increases in average life expectancy

advances in medical care also boosted average life expectancy over the 20th century

advances in sanitation and nutrition probably contributed to advances in life expectancy during the preceeding centuries

women tend to live 4 to 7 years longer than men, although this difference is decreased in industrialized nations

life expectancy varies with SES, ethnicity, and nationality BUT:

life expectancy in late adulthood shows decreased differences between males and females, and among ethnic and SES groups; possibly reflecting attrition of less healthy individuals (Remember: only the survivors get old: What infenences/hypotheses might you draw from decreasing SES/ethnic/sexual differences in death rates in the old old and oldest old?)

chronological age is an imperfect indicator of "functional age": the actual competence and performance of the older adult

"Average healthy life expectancy" refers to the number of years a person born in a particular year can expect to live in full health, without disease or injury

Japan currently ranks first in average healthy life expectancy, in part due to low rates of obesity and heart disease, and favorable health care policies

in developing nations with widespread poverty, disease, and armed conflict; average life expectancy is about 50 years

Factors in a long life:



freedom from exposure to acquired diseases, toxins, pollutants

healthy diet, normal weight


low substance use


low stress

social support

community involvement

life long learning

Quality of life

"activities of daily living" (ADL's) refer to basic self-care tasks needed to live independently (bathing, dressing, managing medications, keeping appointments, transportation). Some discussions consider ADL's in two classes: basic self-care and "instrumental activities of daily living" (paying bills); but many discussions tend to consider ADL's as a whole.

ADL's may be much more situational they we commonly realize: why microwave ovens are the greatest invention of all time

the "Third Age" refers to a current view that old age is a time of potential growth rather than decline; sometimes characterized as the "good news" about aging

increased life expectancy

substantial potential for physical and cognitive fitness

evidence of cognitive and emotional reserves

high levels of emotional and personal well-being

effective strategies to master the gains and losses of later life

the "Fourth Age" refers to the "oldest old" who are at the limits of their functional capacity; sometimes referred to as the "bad news" about aging

sizeable losses in cognitive potential and ability to learn

increases in negative effects of chronic stress

high prevalence of dementia, frailty, multiple chronic conditions

problems with quality of life and dying with dignity

"Maximum lifespan": the genetic/biological limit to the life of a person (excluding external risk factors)

for most of us it appears to be between 70 and 110, with 85 being a commonly cited average

approximately 120 years of life appears to be the upper limit on human life span, although this continues to be a point of debate among scientists

Physical Changes

Nervous system

the aging of the central nervous system affects a wide range of complex activities in the older individual

brain weight declines throughout adulthood, but the loss becomes greater beginning in the 60's due to death of neurons and enlargement of ventricles within the brain

structural changes in the neuron that reduce the effectiveness of information transmission and processing by neurons

neurofibillary tangles -- spiral-shaped masses formed when fibers that compose the axon become twisted together

neurotic plaques -- structural changes produced when damaged and dying neurons collect around a core of protein

dendritic changes -- reduction of dendritic branching

decline in neurotransmitters

Parkinson's disease is caused by insufficient levels of dopamine, often treated with L-Dopa

growth of neural fibers in healthy older adults occur at similar rates as in middle-aged adults

elders who do well on complex cognitive activities (memory, problem solving) tend to show more widely distributed neural activity across the cerebral cortex--this is usually interpreted as their compensating for neuron loss by recruiting additional brain areas to support cognition

the autonomic (peripheral) nervous system, involved in many life support functions, also performs less well with age--putting the elderly at risk during heat waves and cold spells

Sensory systems


several changes lead to increasing problems with vision

lens become more yellow, causing poorer color discrimination in the green-blue-violet end of color spectrum

presbyopia: difficulty seeing close objects clearly

cataracts, opaque spots, develop on lenses of eyes

diseases and abnormal process may also damage vision

if fluid in the eye does not drain properly, glaucoma may result, glaucoma (untreated) can lead to blindness

diabetes can cause abnormal aging of arteries, with blindness being one of the serious side effects

hearing: presbycusis, reduced sensitivity to high frequency sounds

olfactory: sense of smell remains largely intact until after age 70, when declines are often seen

decreased vestibular sensitivity (and decreased muscle strength and response times) make older individuals increasing likely to fall

falls (and decreased bone density) lead to broken bones (often hips) lead to placement in rehabilitation facilities lead to (sometimes) loss of functional skills and ADL's lead to (worse case) loss of home placement lead to (worse case) premature deterioration and (sometimes) death

balance enhancing activities (T'ai Chi) lead to fewer falls, & weight bearing exercise lead to preserved bone density; lead fewer falls, fewer breaks, fewer nursing home placements, etc.

Cardiovascular and respiratory systems

aging in the cardiovascular and respiratory systems (in the absence of disease) tends not to be markedly apparent until late adulthood

decreased blood flow limits the oxygen delivery to body tissues during high physical activity

Immune system

as the immune system ages, T cells, which attack antigens directly, become less effective

immune system malfunctions become more frequent, "autoimmune responses" or "autoimmune diseases" reflect the immune system attacking normal body tissue

decrease immune system efficiency increases the risk for a variety of diseases in the elderly


older adults appear to require approximately the same amount of sleep as younger adults, around 7 hours a night

increased difficulty with falling asleep, staying asleep, and sleeping deeply is reported in the elderly and seen in sleep lab studies

these problems may reflect changes in the brain systems controlling sleep, and by higher levels of stress hormones in the bloodstream

restful sleep can be enhanced by "good sleep habits": consistent bedtime and waking time, using the bedroom only for sleep and sex, regular exercise

prescription sedatives (sleep medications) can help relieve temporary insomnia but long-term use is often problematic

The compression of morbidity hypothesis (originally proposed by Fries, 1980)

human life span is relatively fixed

advances in hygienics, nutrition, and medicine has increased the age at first infirmity

therefore the duration of infirmity will decrease

V. Consequences, Compensations, and Responses

Consider the issue of speech comprehension in the elderly