Theories of aging include psychological, sociological, and biological perspectives. Psychological theories focus on personal development and success, like Erikson's stages of psychosocial development. Sociological theories emphasize engagement through activities, relationships, and experiences. Biological theories propose that aging results from damage accumulation over time, such as from free radicals, genetic factors like telomere shortening, or gradual imbalance between systems. While no single theory explains all aspects of aging, maintaining overall wellness through nutrition, exercise, social engagement and calorie restriction may help optimize health and function in late life.

1. Early Theories of Aging
Thanatophobia
Extend maximum life span
Hippocrates – gradual loss of body heat
Erasmus Darwin – reduced responses to stimuli, loss of
excitability
Others – metabolic rate, irradiation, genetics
“geriatrics” coined in 1914
First geriatric medical journal published in 1945
ACSM founded in 1954
NIA created in 1974

2. Theories of Aging
Psychological
◦ Maslow’s Hierarchy of Needs (1943)
◦ Erikson’s Psychological Stages (1956)
◦ Selective Optimization with Compensation (SOC, 1980)
Sociological
◦ Activity
◦ Continuity
Biological
◦ Damage
◦ Genetic
◦ Gradual Imbalance

3. Theories of Aging
Psychological
◦ Primarily related to success
◦ Personal development
Sociological
◦ Engagement
◦ Experience & environment

4. Maslow’s Hierarchy of Needs:
Theory of Successful Aging

5. Theories of Aging
Erikson’s
Psychosocial Stages
◦ Development through late adulthood
◦ Positive/Negative Outcomes
Late
Adulthood
◦ Pride & satisfaction vs. lack of
accomplishment
◦ Dignity & acceptance vs. frustration
Keys:
close relationships; productivity
with family and/or work; evaluation of the
rear view

6. Theories of Aging
Selective
Optimization with
Compensation (Baltes & Baltes, 1990)
◦ Select priorities/likes/most important
◦ Optimize skills and talents
◦ Compensate for decrements in ability
Examples
◦ Playing music
◦ Lifting weights
◦ Running

7. Theories of Aging
SOC
◦ Functional competence is key
Related
◦
◦
◦
◦
concepts
Self-efficacy (Bandura, 1977)
Self-esteem
Control
Cognitive capacity

8. Theories of Aging: Sociological
Activity
Theory (Havighurst, 1961)
◦ Engaged in mental and physical activities
◦ Community/family/profession
Continuity
(Atchley, 1971)
◦ Carry forward positive habits, relationships,
regardless of advancing age
Can
social beings successfully age without
solid social connections?
Cognitive function?

9. Theories of Aging

10. Theories of Aging
Damage
from wear and tear
◦ Chemical reactions that occur naturally in the
body begin to produce a # of irreversible
defects in molecules.
◦ What is the source of “microinsults”?




Physical
Chemical
Infectious
Mechanical
Loss of function &
System failure
Injury
Repair

11. Theories of Aging

12. Theories of Aging
Free-radical
theory (damage)
◦ Chemical compounds that contain an
unpaired electron in an outer orbital
◦ Able to link to tissue and cause damage

13. Theories of Aging
 Mitochondrial
respiration–
“leaking intermediates”
 Superoxide dismutase

14. Theories of Aging
Free
radical targets
◦ Cell membranes
◦ DNA & RNA
◦ Enzymes
Damage
to tissues, ultimately systems

15. Theories of Aging
Accumulation
of defects in metabolic
pathways
Does aging originate in the mitochondria?
Oxidation of mitochondrial DNA
Widespread impact

16. Theories of Aging
Strategy
for reducing free radicals:
◦ Consumption of Vitamins E and C
 “anti-oxidants”
◦ Mechanism?
◦ Use of supplements?

17. Theories of Aging
Cross-linkage
(damage)
◦ Corrupted DNA not repaired
◦ Cross-linking occurs in protein-based collagen
fibers
◦ Over time, results in





Stiffening of tissue
Rigidity of blood vessels
Tight ligaments & tendons
Cataracts
Atherosclerosis

18. Theories of Aging
Genetic
theories
◦ Genes related to
pathologies
◦ Could dictate cellular aging
◦ DNA mutations of
mitochondria build during
lifetime

19. Theories of Aging

Hayflick Limit
 Cells
will divide & reproduce only a limited
number of times “Cell Clock”
 Number is genetically programmed
 Limitations

20. Theories of Aging
Telomere
Hypothesis
◦ Shortens with each replication
of the chromosome
◦ Replication at a fixed rate may
indicate that the telomere is
the “clock” that determines the
lifespan of any given cell
◦ Dolly’s fate

21. Theories of Aging
Gradual
Imbalance Theory
◦ Nervous system
◦ Endocrine system
◦ Impaired relationship btwn the two
Hormones
impacted
Adaptation impaired
Is aging the result of decreased ability to
survive stress??

22. Theories of Aging
There is no overwhelming support for
just one biological theory of aging.
Likely theories overlap and each explain
some aspect(s) of aging

23. Slowing the Aging Process
Improve
nutrition
↓ total food consumed
Maintain general activity levels
Have social/community
involvement
Perform moderate amounts of
physical exercise

24. Slowing the Aging Process
Caloric
restriction
◦ Total amt of food is reduced
 How much?
◦ Major nutrients, minerals, & vitamins
necessary for health are maintained

25. Slowing the Aging Process
Biosphere
2 experiments
N = 8; ~2 years
Lower
◦
◦
◦
◦
◦
◦
Metabolic rate
Body temperature
SBP & DBP
Blood glucose
Insulin
Thyroid hormones
Okinawan
population
Experimental data in humans?

26. Slowing the Aging Process
General
◦
◦
◦
◦
activity level
Active in life
Social contacts
Taking care of self
Living the “good life”

27. Role of PA/Exercise/Sport?
Compression
of morbidity?
Decrease premature mortality?
SOC?
Social opportunities?

28. Quality of Life
The difference between active living
& just being alive.
Active
life expectancy

29. Quality of Life (more to come)
Activities
of Daily
Living (ADLs)
◦
◦
◦
◦
◦
Walking
Dressing
Bathing/toileting
Eating
Getting up from a
bed or chair
Instrumental
Activities
of Daily Living (IADLs)
◦ Managing finances
◦ Using the telephone
◦ Light housework
◦ Heavy housework
◦ Meal preparation
◦ Shopping
Spiritual health: Relationships,
values, purpose

30. Summary
Factors
that optimize
successful aging:
◦ Avoiding disease
◦ Engaging in life activities
◦ Maintaining high cognitive and
physical function