Predictors of Aging Biological, Psychological, and Sociological

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This article was edited and updated on December 23, 2021.

Successful Aging

Because of many advances in science and medicine, food production and delivery, and sanitation, in general people live longer than they used to. But living longer does not necessarily mean "living better." How, then, do we define "successful aging"?

Researchers have defined "successful aging" in various ways, such as:

While most of us can agree that having all of the things listed above would perhaps define "successful aging," there are people who fit perhaps on either side of the scale — those who do not have all of these characteristics, yet are happy, and those who have all of these characteristics, yet are not happy.

As well, there are individuals who may be successful at one thing — and it becomes a headline story about a 90-year-old who still runs marathons or a 100-year-old who does crossword puzzles every day — but the rest of us should not despair from this either. People are different and not everyone will run a marathon at 90, nor win a world-class chess tournament at 100.

What must be included in any definition of "successful aging" is the quality of a person's life — not just physical health, but also one's state of mind. Therefore, a person's lifestyle will very much contribute to a successful aging process.

There are three theories of aging to be discussed here: Biological, Psychological, and Sociological.

Biological Theories of Aging

The oldest verified person was a French woman named Jeanne Calment, who lived to be 122 years, 164 days old. Worldwide, there are 100 people listed on Wikipedia who are verified as living to somewhere between 114 to 120 years.

Very few people live that long, of course, so the question has to be asked: Why? What may determine our eventual death and why do people age at different rates? There are several biological theories that try to answer those questions. Remember that these are just theories and thus they are still being tested — it is not always possible to separate causes from effects. Further research will no doubt ultimately discover new ideas.

There are three biological theories of aging: Genetic, Damage, and Gradual Imbalance.

Genetic Theories:

These theories focus on the role of heredity. Few genes actually control the rate of aging, but thousands of genes have a role in the development of diseases. It is believed that those genes will ultimately cause our death.

Another theory suggests that aging is controlled by a "biological clock" that is programmed into each cell of your body. As a result, cells will not continue to grow and divide beyond a certain point in time.

Damage Theories:

These theories — which are very complex and technical — suggest that the cells are damaged by an accumulation of DNA errors (known as cross-linkages), waste products, glucose, or free radicals. Going to the cellular level, these theories suggest that an accumulation of cellular damage will increase a person's risk for any number of diseases.

Gradual Imbalance Theories:

In these theories, there is an assumption that different body systems age at different rates, which obviously causes an imbalance in biological functions. Essentially, one part of the body may "die" before another. But if one part of the body doesn't work, it's difficult for the entire body to continue.

Scientists will no doubt continue to explore these various theories to try to find the answers as to why our bodies slowly deteriorate. There is some disagreement about just how much genetics determine the aging process, but it is generally believed to be between 30 and 40 percent 6.

Psychological Theories of Aging

There are three prominent psychological theories of aging discussed here. All attempt to explain a person's psychological development and how that relates to their well-being and the aging process.

Maslow's Hierarchy of Needs:

Maslow's Hierarchy of Needs represented as a pyramid. (Thanks to Wikipedia for the diagram.)

Maslow identifies basic needs that must be satisfied in order for us to live successfully. He's not the only one to have done this; William Glasser also established a Control Theory and came up with five basic needs.

Maslow stated that lower-level needs (hunger, for instance) had to be satisfied first before higher levels can be developed.

Higher levels include things such as finding self-fulfillment and realizing one's potential (known as self-actualization) as well as helping others find self-fulfillment (known as transcendence).

The diagram above puts these needs in a slightly different way, by forming it into a pyramid.

Although there are many disagreements about what needs have to be met before one reaches the higher levels — and even disagreements about the terms — most agree that basic needs must be fulfilled first before going to higher levels. One can see that if basic needs of food, shelter, and clothing are not met, then it is not likely a person will ever be able to reach a higher potential.

Erikson's Psychosocial Stages of Development:

Eric Erickson developed a theory of personality development which goes through eight stages; each stage is characterized by some type of emotional or mental crisis which must be resolved for successful aging to occur.

Erikson's stages are:

If a person gets stuck at any one of these stages, it is more likely (according to this theory) to cause an earlier death than expected.

Wikipedia has a thorough article about Erickson's theory and a more detailed chart of the stages.

Baltes and Baltes' Theory of Selective Optimization with Compensation:

For more details on this theory, read their book.

According to Baltes and Baltes' theory, successful aging has much to do with the ability of an older adult to adapt to physical, mental, and social losses in later life.

Their theory focuses on three life-management strategies for maintaining functional independence in later life:

Key Predictors of Successful Aging:

Pelletier (Sound Mind, Sound Body in 1994, at left below), and Rowe and Kahan (Successful Aging in 1998, at right below) wrote books that discussed the research findings and identified key predictors of successful aging. These include:

Sociological Theories of Aging

Sociological theories consider a person's environment: Is it clean? Is there enough food? Is there support from family and friends? Are there physical as well as mental activities to stimulate both body and mind? The research seems to suggest that these things will make a difference in how well a person ages.

There are two well-known theories:

Since there is plenty of evidence that a person's social and physical environment can influence the aging process, most of us can see the validity of these two theories. 9

There are studies which support these things: In one, positive cumulative social experiences and emotional supports are associated with lower biological risk for morbidity and mortality. 10 Conversely, other studies seem to prove that inadequate social and physical environments are associated with an increase in mortality and morbidity and a decrease in overall health and well-being. 11

How much does Physical Activity contribute to Successful Aging?

There is a great deal of scientific evidence that physical activity is a key ingredient for healthy aging of body, mind and spirt. 12

As for longevity, one study 13 found that fitness level was the best predictor of premature death. Men and women with low fitness levels were twice as likely to die during an eight-year follow-up period than more fit persons.

Looking at each of the three areas — body, mind, and spirit — here's why physical activity is considered to be one of the main determinants of successful aging.

The Body:

There is much research to indicate that those who participate in regular physical activity have lower morbidity and mortality rates than those who are sedentary. Since two of the main indicators of successful aging are longevity and low risk for disease and disability, it would appear that physical activity will help a person stay healthy. 14

An American study 15 and an international study 16 both state that "physical activity reduces the risk of developing many chronic diseases and disabilities (including cardiovascular disease, diabetes, osteoporosis, sarcopenia, certain forms of cancer, and mobility issues)."

The Mind:

When we speak of "the mind" in the context of aging, we are mostly talking about memory and cognition, as it is believed that if these things can be maintained in later life, the aging process is easier. We use our mind to perceive, think, reason, imagine, and desire. Without these things, life is not nearly as enjoyable.

Candace Pert, a Ph.D. in pharmacology, said that the mind is not only in the brain but also in every cell of the body. She wrote about this in her book, Molecules of Emotion: The Science Between Mind-Body Medicine. This concept was also discussed by Dr. Christiane Northrup in her book, Women's Bodies, Women's Wisdom. This concept suggests that there is no separation between mind and body, which means that a "gut" reaction is the wisdom of the body and the mind reacting as one.

Mostly through observation, we know that physical activity can improve the mind. From a variety of sources, here is a list of evidence-based benefits of physical activity on the mind: 17

The Spirit:

It is difficult to define spirituality, but most agree that in this context it is not religion. It is more about an inward and insightful relationship with oneself and with others. It includes a strong personal value system. Most importantly, there is a sense of meaningful purpose in life.

There is little research on the impact of physical activity on spiritual health, 18 but many researchers believe that physical activity can help people to connect to and enhance their spiritual growth.


Successful aging is a unique experience for each individual. We have control over some of it, yet little-to-no control over, for instance, our genetics. What seems to be certain, however, is that physical activity can definitely help us to lead healthier, happier lives. And perhaps longer lives.

Primary Source for this article:
Chapter 2 of Physical Activity Instruction of Older Adults,
by C. Jessie Jones, PhD, and Debra J. Rose, PhD, 2005.

I am a BCRPA-certified fitness instructor in Vancouver, BC. I teach four classes at the West End Community Centre in Vancouver, BC, mostly designed for the older adult. The Inevitable Disclaimer: Everything published here expresses only my opinion, based on my training and research. What you do with the information is entirely your own responsibility. I am not liable for any injury you suffer that seems to be related to anything you read here. Always consult your doctor before beginning an exercise program. For other articles, return to the table of contents.

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  1. These three dots behave exactly like a footnote. Click on them and you will get more information about the topic. ↩︎

  2. Havighurst, 1961 ↩︎

  3. Palmore, 1979 ↩︎

  4. Rowe and Kahn, 1987 ↩︎

  5. from a variety of researchers ↩︎

  6. Rowe and Kahn, 1998 ↩︎

  7. Fisher, 1995; Lemon, Bengtson & Peterson, 1972 ↩︎

  8. Atchley, 1972 ↩︎

  9. Lemon et al, 1972; Sugtswawa, Liang & Liu, 1994; World Health Organization, 1998 ↩︎

  10. Seeman et al, 2002 ↩︎

  11. House, Landis & Umberson, 1988; Seeman & Crimmins, 2001; Seeman et al, 2002 ↩︎

  12. American College of Sports Medicine, 1998; Robert Wood Johnson Foundation, 2001; US Department of Health and Human Services, 1996, 2000; World Health Organization, 1998 ↩︎

  13. Blair et al, 1996 ↩︎

  14. Rowe and Kahan, 1987 ↩︎

  15. Robert Wood Johnson Foundation, 2001 ↩︎

  16. Bouchard, Shephard & Stephens, 1994 ↩︎

  17. Chopra, 1993; Pelletier, 1994; Stathi, Fox and McKenna, 2002 ↩︎

  18. Crowther, Parker, Achenbasum, Larimore & Koenig, 2002; Pelletier, 1994; Leder, 1997; World Health Organization, 1998 ↩︎