Physical Development in Adulthood

Meaning of Physical Development in Adulthood

By the mid-twenties, physical development reaches its peak in health, strength, and stamina, except for slight fluctuations in height and weight. From there, physical health slowly begins to decline throughout adulthood. Around the age of 30-35, the aging process begins. As people age, the tips of their chromosomes, called telomeres, start to wear away and initiate the aging process.

Life expectancy has drastically increased from 1950 to 2015, changing from 46.5 in 1950 to 71 years in 2015. Additionally, women are more likely to outlive men worldwide. As a result of increased lifespans, more people are reaching older adulthood than ever before in recent human history.

Characteristics of physical development in adulthood

While many people continue to live healthy and active lives even in older adulthood, aging causes several changes in physical development in adulthood. Characteristics of physical development in adulthood include:

• Weight gain

• Vision loss

• Slower mental processing

• Fragile bones

• Diminished muscle strength

• Decreased reaction time

• Disruptions in sexual arousal

• Hearing loss

• Memory decline

• Weakened immune system

These changes are the most prominent in the later years of life. They can be so subtle in early and middle adulthood that they are barely noticeable in daily life. However, in late adulthood, aging speeds up, and changes happen more noticeably.

Process of Physical Development in Adulthood

Physical development in adulthood looks different in early, middle, and late adulthood. The process of physical changes ranges from the peak of young adulthood to the end of life.

Early Adulthood (19-40 years)

Early adulthood, or the "prime of life," marks full maturity and peak physical performance. Vision, muscle strength, hearing, reproductive ability, motor ability, and lung strength are all at their best in our mid-twenties. Physical development may begin to decline towards the end of early adulthood (ages 30-40), but it remains mostly unnoticeable. It can fluctuate due to things like diet, exercise, and pregnancy.

Middle Adulthood (40-60 years)

The decline of physical development starts becoming more noticeable in middle adulthood. Middle-aged adults might notice that some physical tasks are more difficult than before. The female reproductive system undergoes a major change when it reaches menopause, while the male reproductive system remains pretty much the same. Physical changes in middle adulthood tend to have a significant psychological impact. These physical changes signal that an adult has reached the second half of life and likely has less time to live than the years that have already passed.

Late Adulthood (60-death)

Physical development in adulthood continues declining into later life and becomes more pronounced. Aging sets in fully, and chronic illnesses become more common. Memory and other cognitive abilities often suffer the most significant declines, sometimes through neurological diseases such as Alzheimer's and Parkinson's. Changes in physical appearance such as wrinkles, gray hair, and yellowed teeth become very noticeable.

Fig. 1 Late adulthood, pikwizard.com

Challenges of Physical Development in Adulthood

Physical development in adulthood comes with several challenges due to aging, including tissue loss in the brain, changes in the reproductive system (primarily for women), and changes in sensory abilities. Adults also experience a general decline in physical stamina.

Brain Challenges

As we age, the connections in the brain are more established, but brain cells begin to die, resulting in tissue loss in the brain. In early adulthood, neurogenesis is still possible, but this process declines rapidly as you age. Only a few areas in the brain remain capable of neurogenesis as we age: the hippocampus and the lateral subventricular zone.

Tissue loss or atrophy in the brain is typically most present in the frontal lobe of an aging brain. This part of the brain develops fully in adolescence and young adulthood and is responsible for important functions such as impulse control. The atrophy in the frontal lobe could explain why older adults are known to ask blunt questions or offer unfiltered responses.

A common characteristic of aging in adulthood is cognitive memory decline. Regions in the brain responsible for memory also begin to atrophy during old age. Even though neurogenesis can still occur in the hippocampus of an aging brain, it may not be able to make up for the damage caused by deterioration in other areas.

Reproductive system challenges

As people age, their reproduction begins to change. This is especially true for women. The chances of getting pregnant drastically decline by the age of 35. By around 50 years old, menopause begins, but the age of onset varies widely from one person to another.

During menopause, a woman's sex hormone levels decline, her ovaries stop releasing eggs, and her chances of becoming pregnant are slim to none. The timing of menopause can be influenced by several biological, environmental, medical, and psychological factors. Women who had surgery to remove one or more ovaries may start menopause sooner than others. If a woman undergoes a hysterectomy (the complete removal of the uterus), menopause will begin immediately.

Changes in the reproductive system are far less drastic for men. As men age, their sperm count and testosterone levels slowly decline, but they remain able to produce offspring well into old age. The sperm of older men may carry abnormalities, though, that can cause birth defects. Genetic mutations in sperm are one possible cause of the increased prevalence of autism in the offspring of older males.

Sensory abilities

Another challenge of physical development facing adults is declining sensory abilities. Visually, older adults may require more light to see well as their pupils shrink and the eye's lens becomes less transparent.

As a result, older adults can have difficulty driving at night or with tinted windows. Perceiving distance becomes more difficult and causes challenges in reading smaller text, requiring the use of reading glasses.

Hearing also declines. The ability to hear high-pitched sounds is the most affected. This is why ringtones specifically designed for younger people are high-pitched. A high-pitched ring played outside a restaurant to discourage juvenile loitering leaves older adults unbothered.

Strength and stamina

Physical development in adulthood also involves changes in strength and stamina. Sarcopenia, the loss of muscle tissue and function, sets in as we age. Older adults, especially women, may develop a disease called osteoporosis.

Also more common among women than men is a disease called rheumatoid arthritis (RA). Antibodies attack the fluid surrounding the joints, causing pain and stiffness. The immune system weakens as we age, making us more prone to illnesses. The onset of diseases such as cancer or heart disease in adulthood can significantly affect a person's physical strength, ultimately leading to other physical complications or death.

Fig. 2 Aches and pains, freepik.com

Factors affecting physical development in adulthood

Several factors can affect physical development in adulthood. Genetics can play a large role in life expectancy and a general decline in physical stamina. We don't really have control over what genes we receive from our parents, but there are other factors that affect physical development in adulthood that we can control such as exercise.

Exercise is important for every stage of physical development. But in adulthood, it can slow aging. The increased oxygen and nutrient flow produced by exercising can reduce cognitive decline by strengthening neural connections and reducing brain cell death. Exercise also reduces brain shrinkage and helps improve memory by promoting neurogenesis in the hippocampus, the region of the brain responsible for memory formation.

Additionally, exercise can enhance muscle strength and bone health in adulthood and helps prevent obesity and heart disease. We mentioned earlier that the shortening of telomeres is responsible for aging. Exercise can help maintain the telomeres, protecting chromosome ends and slowing aging, even the progression of Alzheimer’s disease.