Healthy lifestyles incorporating physical activity (PA) and exercise have been shown to be highly beneficial for persons aged 75 and older. Reductions in functional decline (frailty), coronary heart disease (CHD), and disability before death along with increased life expectancy have all been demonstrated.^1,2,3,4,5 Specific exercise programs have also been shown to prevent falls in the elderly^6,7,8 and improve function and quality of life in individuals with osteoarthritis (OA).^9,10,11,12 Lack of activity is often underappreciated as a cause of death, but it has been shown that it causes twice as many deaths as is attributable to obesity.¹³

Table 42.1 describes the 2018 Physical Activity Guidelines for Americans, second edition⁵ for activity in older adults. A recent Surgeon General’s report indicates that only 22% of adults in the United States are active enough to derive benefits from activity.¹⁴ According to the World Health Organization (WHO), globally, 23% of adults and 81% of adolescents (aged 11-17 years) do not meet the WHO global recommendations on physical activity for health.¹³ Meanwhile, the American College of Sports Medicine (ACSM) and the Centers for Disease Control and Prevention (CDC) recommend that all Americans should engage in a minimum of 30 minutes of moderate PA daily.¹⁵ The National Institutes of Health also issued similar recommendations.¹⁶

In a landmark report, the Surgeon General of the United States stated that older people regardless of gender or socioeconomic class are not exercising as much as they should, with women generally less active than men; 30% of women ages 60 to 69 engage in no leisure time activity compared with 17% of men.¹⁴ In 80-year-olds, 62% of women and 40% of men engage in no leisure time activity. The Surgeon General calls for at least 30 minutes of PA per day.

PA as well as other identifiable lifestyle factors play a role in life expectancy. Five “low-risk” factors were identified: never smoking, body mass index (BMI) of 18.5 to 24.9, greater than 30 minutes per day of vigorous PA, moderate alcohol intake, and high diet quality score. Individuals with all five low-risk lifestyle risk factors compared with individuals who have zero low-risk lifestyle factors at the age of 50 are predicted to add 12 to 14 years additional life expectancy.¹⁷

According to the 2018 Physical Activity Guidelines for Americans, second edition,⁵ “Even low amounts of moderate-to-vigorous intensity physical activity
reduce the risk of all-cause mortality.” The greatest benefit occurs when a person ceases being inactive^5,18 (see Fig. 42.1). More activity is not only beneficial but also safe, “The relative risk of all-cause mortality continues to decline as people become even more physically active. Even at very high levels of physical activity (three to five times the key guidelines), there is no evidence of increased risk.”⁵

Inactive men 60 years of age who become active have a mortality rate 50% lower than their peers who remain inactive.¹⁹ A study of Harvard University alumni confirmed this result. Men who were initially sedentary but later began engaging in vigorous sports had a 23% lower rate of mortality than their inactive counterparts.²⁰ A Honolulu Heart program found that retired men who walked more than 2 miles per day had half the mortality rate (22%) than those who walked less than 1 mile per day (43%).²¹ A follow-up study by Hakim reported that men who walked less than 0.25 miles per day had a 2-fold increased risk of CHD than those who walked 1.5 miles per day. Also, men who walked more than 1.5 miles per day experienced even greater preventive benefit. Women have also been shown to reduce their risk of cardiovascular (CV) disease from walking.²

There is a strong relationship between time spent in sedentary behavior and the risk of all-cause mortality and cardiovascular disease (CVD) mortality in adults (Fig. 42.2).^5,22 Red represents higher risk of all-cause mortality, and green represents lower risk of all-cause mortality.

It is imperative that public health education and physician-led patient education initiatives spread this knowledge. Implementation, dissemination, and advocacy are needed to change behavior. Many physicians counsel patients about smoking and body
weight, but not about inactivity.²³ In the past, it was believed that unless exercise intensity was fairly high (60%-80% maximal heart rate), health benefits would not accrue. A 3- to 4-mph walk is now acknowledged as beneficial.²⁴ Additionally, exercise does not have to be at one time; therefore, for instance three 10-minute walks will be of benefit.²⁵

The factors that limit physical performance in the elderly are either immutable or modifiable. Immutable characteristics include such things as gender, race, age, or chronic health problems. Modifiable include behavioral (i.e., moderate exercise), social network characteristics, and psychological characteristics (i.e., self-efficacy beliefs) (see Chapters 13, 14, 15).⁴ Both physical exercise and emotional support from one’s social network predict physical performance over a 2.5-year follow-up period.⁴ In fact, moderate activities (leisure walking) are as effective as strenuous activities (brisk walking). Compliance with PA prescription is improved with group fitness according to a systematic review of group walking participants. Group walking participants were shown to have improved PA on follow-up when compared with those walking alone or inactive controls and reported better quality of life. Further studies may encourage government policy to promote walking in groups.²⁶ It is widely recognized that social relationships and affiliation have powerful effects on physical and mental health. Provision of social support, social influence, social engagement and attachment, and access to resources and material goods are four primary pathways through which social networks affect behavioral pathways.²⁷ Lifestyle behavior change has also shown to be effective for individuals with chronic pain in terms of both outcomes and reducing the socioeconomic burden related to chronic pain and other noncommunicable diseases.²⁸

The Recent American guidelines⁵ state, “The benefits of regular physical activity occur throughout life and are essential for healthy aging. Adults ages 65 years and older gain substantial health benefits from regular physical activity. However, it is never too late to start being physically active.” Being physically active makes it easier to perform activities of daily living (ADLs) such as—

Physically active older adults derive numerous benefits such as—

The Guidelines continue,⁵ “Research shows that physical activity can improve physical function in adults of any age, adults with overweight or obesity, and even those who are frail.” Older adults spend a significant proportion of their day being sedentary even though “physical activity is key to preventing and managing chronic disease.”⁵ Additional benefits include a reduced risk of dementia, depression, or anxiety.

The Functional Assessment Scale (see form in Chapter 8) has been developed for assessing functional levels in older adults with OA of the knee(s).²⁹ It was devised from the mobility and PA components of the Arthritis Impact Measurement Scale,³⁰ which has been shown to be reliable and valid.³¹ This form could also have utility for measuring functional status in any elderly person with lower quarter musculoskeletal pain or limitations, balance issues or frailty, or those with specific functional limitations relating to standing, walking, stair climbing, including those requiring aids such as a cane or crutches.

According to Merriam-Webster, the term life span is defined as the average length of life of an organism or of a material object. Health span refers to the length of time a person is healthy, not just alive.³² Globally, life span has increased significantly in the last two decades. From 1990 to 2017, life expectancy at birth increased by 7.4 years, from 65.6 years in 1990 to 73.0 years in 2017.³³ The increase in longevity varied from 5.1 years in wealthier countries to 12.0 years in poorer countries. Of the additional years of life expected at birth, 26.3% were expected to be spent in poor health in wealthier countries compared with 11.7% in poorer countries.³³

The 2010 Census Bureau data (Fig. 42.3) show a dramatic increase in life expectancy at birth since 1900 (47-79 years).³⁴ Figure 42.4 demonstrates that between 2000 and 2020 it is estimated that the 55- to 64-year-old
and 65 and up age group are increasing by 73% and 54%, respectively, whereas all younger age groups are at most only increasing by 8%!³⁴ WHO estimates that from 2000 to 2050 the number of people 60 years or older will double, and that over 20% of the world’s population will be 60 years or older³⁵ (Fig. 42.5). So much so that 2017 Census Bureau estimates that the shape of the population distribution which has always been a pyramid with children outnumbering the elderly will switch to a pillar by 2060 (Fig. 42.6).³⁴

According to GBD (2017), “With increasing life expectancy in most countries, the question of whether the additional years of life gained are spent in good
health or poor health has been increasingly relevant because of the potential policy implications, such as health-care provisions and extending retirement ages.”

As life span has increased worldwide, health span has not proportionately improved and therefore has become of greater concern.^36,37 When life span was shorter, the percentage of life spent with suboptimal integrity of the musculoskeletal system was smaller.³⁸ As demonstrated in Figure 42.7, life span has grown much more than health span thus leaving us with a much greater time of life living with disability.³⁸

A major issue that looms is how to take care of people who live a long life span with a poor health span. According to GBD (2013), “… a shift from communicable to non-communicable causes of disease burden and injuries remains a powerful framework for global and
regional health policy debates …. Even in the most advantageous sociodemographic quintile of countries, the time lived in full health constitutes only a small fraction (17.5%) of the overall life course.”³⁹ Older adults have proportionately more health care problems⁴⁰ (see Fig. 42.8). With an aging population this brings about an emerging crisis. According to a 2016 Consumer Expenditure Survey,⁴¹ people over 50 years old utilize

In spite of large gains made against the majority of leading causes of death in most countries, “these gains are not being accompanied by commensurate declines in age-standardized rates of disability, especially from major musculoskeletal disorders, mental and substance use disorders, neurological disorders, and diabetes.”³⁹ Disease burden is a keystone concept to understand for the Sustainable Development Goal of ensuring healthy lives and promoting well-being across the life span.^33,42

In an era with longer life span, new issues emerging revolve around the age of retirement. Evidence shows the increase in life expectancy is not accompanied by an equivalent increase in years in good health. The disease or disability burden from musculoskeletal disorders and mental disorders has not improved over time.³³

A metric for health span or disease burden is disability-adjusted life years (DALYs) (see Fig. 42.9). This is a measure of overall burden of disease. It adds the years of life lost to early death with the years spent living with disability. Low back pain is the number one cause of DALYs from musculoskeletal conditions (see Fig. 42.10).⁴³ Disability resulting from low back pain is up 54% since 1990 (see Fig. 42.11).^44,45

According to May et al, “Therefore, it is increasingly important to investigate potentially modifiable factors that are related to living longer in good health.” Potentially modifiable factors that are related to living longer in good health include being physically inactive and smoking.^36,37,46 May et al report “that adhering to a healthy lifestyle such as non-smoking, maintaining a low BMI, being physically active, or consuming a healthy diet, results in a lower disease burden.” The modifiable lifestyle factors are³⁶

Other researchers have found similarly that “For each gender and race group, those with the healthiest lifestyle (those who were nonsmokers of a healthy weight and diet and getting regular exercise) not only lived longer, but had fewer disabled years at the end of their lives”⁴⁷ (see Figure 42.12) (on the line).

Another study by Leskinen et al analyzing the relationship between PA and life expectancy revealed a clear dose-response relationship between higher PA levels and increased health and chronic disease-free life expectancy in both men and women. On average, vigorously active men and women lived 6.3 years longer in good health and 2.9 years longer without chronic disease between ages 50 and 75 compared with inactive adults. This difference between vigorously active and inactive individuals was largest in individuals with low occupation status.⁴⁸

It is hypothesized that there is an activity threshold involved in healthy aging. Evidence shows that sufficient activity promotes optimal aging, whereas insufficient activity below threshold leads to uncertain health trajectory and compromises aging. Furthermore, activity levels that are more than sufficient may not provide additional health benefits, but can contribute to maximizing athletic performance⁴⁹ (see Figure 42.12).