EPIDEMIOLOGY of SPORTS and EXERCISE

Resistance training (RT): RT can build muscle strength, lean mass, bone mineral density, strength-endurance, and power, reduce body fat, and improve posture (Fahey, Insel, & Roth, 2018). Resistance can include body weight, elastic bands, water, weights, or weight machines. RT should be performed two to three days per week with a rest day between sessions, and exercises should the major muscle groups in the upper and lower body.

Balance (stability) training: Balance is the ability to maintain the body in a stationary or upright position or moving stance. For OA postural stability is a more specific description of human balance (Rogers, Page, & Takeshima, 2013). Balance training includes strengthening and stability exercises. The strengthening component of balance training includes mostly lower body exercises, performed two to three days per week. Stability training can and sometimes should be performed daily. OA at risk of falling should dobalance training (Chodzko-Zajko et al., 2009) three or more days per week (US Department of Health and Human Services, 2008). Balance training enhances postural stability (Ruffieux, Mouthon, Keller, Wälchli, & Taube, 2017), static postural sway, and dynamic balance (Rogers et al., 2013).

Stretching and flexibility exercises: Flexibility— the ability of a joint to move through its normal, full range of motion—is important for general fitness and wellness (Fahey, Insel, & Roth, 2018). Stretching exercises improve flexibility, minimally increase strength, but do not improve endurance. Older adults should perform stretching exercises after they have completed endurance and strength exercises (Chodzko-Zajko et al., 2009). If they do only stretching and flexibility exercises, they must warm up first with gentle movements or slow walking. Stretching exercises can be performed daily and include shoulder, upper arm, calf, and thigh stretches. Stretching improves range of motion, coordinated movements, and posture, promotes relaxation, and reduces the risk of injury and falling. (Foley, Hillier, & Barnard, 2011)

Physical activity and exercise promote motor control through improved coordination—the ability to use all body parts together to produce smooth and fluid motion; agility— the ability to change direction quickly; reaction time— time required to respond to specific stimuli; speed— the ability to move rapidly; and power— the ability to generate force rapidly. Exercise enhances cognition, concentration, relaxation, and joie de vivre, perhaps by promoting endorphin release (Cherup, et al., 2018).

Exercise programs could also facilitate social interactions between participants which could lead to the enhancement of social health. The latter refers to the ability to interact well with people and the environment and to have satisfying personal relationships. From a holistic perspective, the setting provided by the exercise experience promotes mental, emotional, and spiritual health.

Promoting Exercise Adherence in Older Adults

Age, sex, health status, self-efficacy, motivation and genetics are associated with physical activity (US Department of Health and Human Services, 2002). Genetic and epigenetic factors influence the propensity for physical activity (Bauman et al., 2012; Levine, Eberhardt, & Jensen, 1999). Twin and family studies provide further evidence that genetic factors contribute to variations in daily physical activity levels (Bouchard et al., 1990; Simonen et al., 2002). Epigenetics, heritable changes in gene expression that do not change DNA sequence, might influence adherence (Ursu et al., 2015). Exercise might lead to more exercise, while inactivity might have the opposite effect. An absence of evidence suggests the role of the human genome in adherence to exercise programs.

Abundant evidence shows that physical activity and exercise are among the most important factors influencing health status in the elderly (Chodzko-Zajko et al., 2009; US Department of Health and Human Services, 2002). Regular exercise is associated with increased longevity and reduced risks for cardiovascular disease, stroke, cognitive decline, some cancers, type 2 diabetes, osteoporosis, hypertension, dyslipidemia, obesity and osteoarthritis (Fahey et al., 2018). Exercise programs are also associated with improved psychological health and functional status, and reduced health-care expenditures (Chodzko-Zajko et al., 2009). Physical activity is an elixir vita that promotes health and longevity better than any other lifestyle practice, but it is only effective if people do it. Exercise adherence is a difficult problem for people of any age, but it is challenging in OA.

Among the aims of Healthy People 2010 (US Department of Health and Human Services, 1998) is that professionals, paraprofessionals, and paid and unpaid caregivers need basic and continuing geriatric education to improve care for OA. This informative report is to fill information gaps in the health care spectrum of OA, regarding physical activity, exercise and adherence to programs.

Relevance of Physical Activity and Exercise in OA

Prior to 1980, physical activity recommendations for the general population promoted vigorous exercise that largely reflected the physical fitness requirements of the military and athletes (Fahey & Fahey, 2014). Not until 1975 did advocate groups recommend exercise three to five days per week for fifteen to sixty minutes at 50 to 85 percent of heart rate reserve plus resting heart rate (American College of Sports Medicine, 1975). For the first time, the exercise recommendations focused on the metabolic health and reduced risk of “diseases of civilization” in the general population (American College of Sports Medicine, 1975). Following those recommendations, the body of knowledge and relevance of exercise on health and well-being had an exponential increase, leading to modifications of the exercise recommendations in 1978, 1998, 2007 and 2011 (American College of Sports Medicine, 1978, 1998; Garber et al., 2011; Nelson et al., 2007). Abundant research in the 1980s and 1990s showed that moderate intensity exercise promoted health and longevity. The extent of such findings led to physical activity recommendations from the U.S. Surgeon General (SG) in 1996 (US Department of Health and Human Services, 1996), the US Department of Health and Human Services in 2008 (US Department of Health and Human Services, 2008), a joint publication by the American Heart Association / American College of Sports Medicine in 2007 (Nelson et al., 2007), the World Health Organization in 2010 (World Health Organization, 2010b), and the American College of Sports Medicine in 2011 (Garber et al., 2011). The 2008 publication of the US Department of Health and Human Services presented explicit recommendations for promoting physical activity and health (US Department of Health and Human Services, 2008), while that of the SG in 2010 a Vision for a Healthy And Fit Nation (Benjamin, 2010). Key elements in those reports were the importance of regular physical activity and the novel finding that some physical activity is better than none. These reports stated that regular physical activity promoted health and prevented premature death and many diseases. Physical activity benefited people of all ages, racial, and ethnic groups, including those with disabilities. The recommended levels of physical activity are associated with increased longevity, improved psychological health, functional status, and reduced health-care expenditures. Those reports stated that the benefits of exercise and physical activity out weight the risks.

Healthy People 2020 (US Department of Health and Human Services, 2010), a governmental 10-year agenda for improving the Nation’s health, promotes the physical activity compliance of Americans based on the Physical Activity Guidelines for Americans (US Department of Health and Human Services, 2002). Over 80 percent of the population do not meet physical activity guidelines for aerobic exercise and strengthening activities (Fahey et al., 2018). For OA, Healthy People 2020 aims to improve the health, function, injury prevention (e.g., falls), and quality of life. OA experience higher risk of chronic disease. CDC reports indicate that 60% of OA managed two or more chronic conditions, including heart disease, cancer, chronic obstructive pulmonary disease, stroke, diabetes mellitus, and Alzheimer's disease (Ward, Schiller, & Goodman, 2014). Healthy People 2020 attempts to educate people about the relevance of physical activity and increase the proportion of Americans who meet the physical activity guidelines. Strategies include improving community Infrastructures by increasing the availability of sidewalks, bike lanes, trails, and parks and promoting legislation to improve access to facilities that promote physical activity. Facilities should be accessible to people with disabilities.

What is Adherence, Exercise adherence, and How is it Measured?

The WHO defines adherence as the extent to which a person's behavior corresponds to the recommendations of a healthcare provider (World Health Organization, 2003). These behaviors include taking medications, following a diet, and executing lifestyle changes such as increased physical activity. The WHO stated that “measurement of adherence provides useful information that outcome-monitoring alone cannot provide, but it remains only an estimate of a patient’s actual behavior”. No single measurement strategy has been deemed optimal. A multi-method approach that combines feasible self-reporting and reasonable objective measures is the current state- of-the-art in measurement of adherence behavior (World Health Organization, 2003). The WHO further stated that: 1) poor adherence to treatment of chronic diseases is a serious worldwide problem; 2) The impact of poor adherence grows as the burden of chronic disease grows worldwide, where the poor are disproportionately affected; 3) The consequences of poor adherence to long-term therapies are poor health outcomes and increased health care costs; 4) Improving adherence also enhances patients’ safety; 5) Adherence is an important modifier of health system effectiveness; 6) Increasing the effectiveness of adherence interventions may have a far greater impact on the health of the population than any improvement in specific medical treatments; 7) Health systems must evolve to meet new challenges; 8) Patients should be supported, not blamed. Factors, which make up the health care environment in which patients receive care, have a major effect on adherence; 9) Adherence is simultaneously influenced by several factors (social and economic factors, the health care team/system, the characteristics of the disease, disease therapies and patient-related factors); 10) Providers need to develop means of accurately assessing not only adherence, but also those factors that influence it (i.e., patient-tailored interventions); 11) Adherence is a dynamic process to be followed up; 12) Health professionals be trained in adherence; 13) Family, community and patients’ organizations are a key factor for success in improving adherence; 14) A multidisciplinary approach towards adherence is needed.

Exercise adherence (EA) is ill-defined and ambiguous. Available definitions, usually rely on four measures: 1) Completion/retention adherence; 2) Attendance adherence; 3) Duration adherence; and 4) Intensity adherence (Martin & Sinden, 2001). A recent systematic review of the exercise related literature examined those definitions of adherence to exercise sessions in OA (Hawley-Hague, Horne, Skelton, & Todd, 2016). Completion/retention adherence is the retention/completion of an exercise classes program and attendance. In one instance adherence (completion) implied returning to the program after a 10-wk. (Estabrooks & Carron, 1999). In another study, adherence was full completion of the required attendance and presence in the last session (Sullivan-Marx et al., 2011). Attendance adherence refers to the number of exercise sessions attended over a follow-up period ( Hawley-Hague et al., 2014). A good number of studies define adherence based on absolute attendance while others utilize the percentage of classes attended (Hawley-Hague et al., 2016). It relates to note that percentage was calculated by different ways. Duration adherence considers how long a participant exercise for at each exercise session. Duration of exercise has been determined in an assortment of ways, which include self-reports of exercise performed within and outside the classes, physical activity questionnaires, or surveys, records of minutes physically active, among others (Hawley-Hague et al., 2016). Intensity adherence refers to the specified level of effort (intensity) expected to be attained. Reported intensities can be summarized: at least 20 min of continuous exercise at 55–70% of maximum heart rate, ‘moderate intensity’ as per the prescribed exercise regime, times participants exercised three times a week for 30 min at 60–80% of maximum heart rate. Conceptually, EA is related to biological adaptations, since improvements in functionality are associated with fulfilling the prescribed plan. From an operational perspective EA is the extent to which a person meets the advised interval, exercise dose, and exercise-dosing regimen (Dorgo, King, & Brickey, 2009). The unit of measure for EA is the performed exercise doses per defined period of time reported as a proportion of prescribed exercise doses performed at the prescribed time interval. However, such views of EA are not highly prevalent.

The most common measures of adherence to exercise programs for the OA are (Pavey et al., 2012; Picorelli, Pereira, Pereira, Felício, & Sherrington, 2014):

1. Proportion of participants completing exercise programs,

2. Proportion of exercise sessions attended,

3. Average number of home exercise sessions completed per week,

4. Class attendance expressed as a proportion of participants reaching certain cut offs,

5. Total sessions attended,

6. Number of weeks in which home exercise was undertaken,

7. Proportion of days on which home exercise was undertaken,

8. Number of minutes walked,

9. Proportion of participants meeting physical activity guidelines, and

10. Proportion of participants exercising regularly.

Systematic reviews (Pavey et al., 2012; Picorelli et al., 2014), indicate that the proportion of OA completing group exercise programs ranged from 65% to 86%, proportion of sessions attended fluctuated from 58% to 77%, and the average number of home exercise sessions completed per week ranged from 1.5 to 3 times per week.

Factors Associated with Adherence in OA

Factors associated with adherence to exercise in OA include:

1. Higher socioeconomic and educational levels (Forechi et al., 2018);

2. Living alone (Osuka et al., 2017);

3. Good health (measured by fewer health conditions, better self-rated health, fewer medications) and low body mass index (Fielding et al., 2007);

4. People with pacemakers, reflecting desire for self-preservation (Rejeski et al., 2007). Often, pacemakers are also defibrillators and are set to discharge above a given heart rate. Patients actively avoid these shocks and are adept at determining exercise intensity using heart rate monitors and perceived exertion.

5. Better physical function (Fielding et al., 2007);

6. Fewer depressive symptoms (depression, loneliness, low scores on Mental Status Test, psychoactive medication use and a higher perceived risk of falling), and (Picorelli et al., 2014);

7. Genetic factors influencing physical activity (Bouchard & Hoffman, 2011; Ursu et al., 2015);

8. Extrinsic motivators, such as cash incentives and smartphone applications (Finkelstein, Brown, Brown, & Buchner, 2008; Helbostad et al., 2017)

9. In OA, adherence is higher in supervised programs (LaCroix, et al, 2015)

Table 1 shows a compendium of factors associated with physical inactivity (Allen & Morey, 2010). There is a high probability that non-adherers to exercise programs or non-participants in vigorous physical activity or exercise programs in community based or living facilities settings will comply with at least one factor in Table 1. The absence of evidence suggesting the role of the human genome in adherence to exercise programs do not preclude findings linking daily physical activity levels and the inclination for physical activity with genetic components (Bauman et al., 2012; Bouchard & Hoffman, 2011; Levine et al., 1999; Simonen et al., 2002).

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Table 1 about here

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How is adherence promoted?

Adherence is promoted by the belief that an intervention will be effective (i.e., the outcome expectancy), and the individual can follow the intervention (i.e., the efficacy expectancy) (Flegal, Kishiyama, Zajdel, Haas, & Oken, 2007). People with greater adherence may engage in other health promoting behaviors. Adherence may be a marker for a personality type or related to motivation or goal-directed behaviors.

Self-efficacy, or the perceived confidence in one’s ability to accomplish a specific task, is another relevant factor in promoting adherence (Flegal et al., 2007). It might relate to motivation. Self-efficacy affects exercise adoption and maintenance (Fielding et al., 2007). Intervention programs should develop and nurture this characteristic to enable individuals to continue with a program. The reviewed studies suggest that strategies to promote adherence should include making instructions to subjects simpler and less demanding, addressing cognitive motivational factors such as self-efficacy and health beliefs, offering social support and reinforcement, and providing reminders (Flegal et al., 2007). Appropriate activities should be carefully planned before program implementation to best suit the specific needs of OA. Good communication and continuous motivation might also increase participation (Sjösten et al., 2007). An exercise program should also address behavioral motivation, social and environmental contexts, to raise commitment to exercise among a largely sedentary population of OA with their multiple illnesses and functional deficits (Stineman et al., 2011; Sullivan-Marx et al., 2011).

Adherence to exercise programs and preventing falls

Falls are the leading cause of injury and death from injuries among OA (Bergen, Stevens, & Burns, 2016). According to those CDC records in 2014, older Americans experienced 29 million falls causing seven million injuries and costing an estimated $31 billion in annual Medicare costs. Fall injury rates are almost seven times higher for OA with poor health than for those with excellent health. Increased inactivity, reduced muscle strength, more severe chronic health conditions, and increased use of prescription medications are risk factors for falls among OA. When assessing the effects of fall prevention programs, the overall adherence rates range from 67% to 73% in-group exercise sessions (Clemson et al., 2004; Tinetti et al., 1994) and 70% to 90% in home-exercise programs (Campbell et al., 2005; Lord et al., 2005).

The predictors of adherence in fall prevention programs are poorly understood, and few predictors have been identified (Cumming et al., 2001; Hornbrook et al., 1994). These include a person’s beliefs about the possibilities to prevent falls by the activities of the program and home modifications to prevent falling (Cumming et al., 2001). OA at high risk of falling have the highest attendance in these programs due to their higher intrinsic motivation to prevent catastrophic accidents (Hornbrook et al., 1994). Such findings support the Health Belief Model (HBM) (Champion & Skinner, 2008). The HBM addresses the relationship between a person’s beliefs and behaviors. It provides a way to understanding and predicting how “clients” will behave in relation to their health and how they will comply with health care therapies. The best exercises for preventing falls have not been identified. OA lose type 2 motor units with age. These structures respond best to high speed overload (Power et al., 2016), but these exercises might not be well received in this population. Yet, high intensity training is associated with increased patient compliance and is suitable for implementation in both healthy and 'at risk' populations (Reitlo, et al., 2018; Oliveira, et al., 2018).

High Intensity Exercise Training

High speed overload training commonly used in OA programs include modifications of traditional aerobic exercise (cardiorespiratory endurance) and resistance training (RT) programs. Traditional aerobic exercise consists of continuous, moderate-intensity training (MICT). HIIT involves repeated high intensity exercise bouts of 30 seconds to several minutes, separated by 1-5 minutes of recovery. An advantage of HIIT over MICT is the shorter time required to perform the same energy expenditure. High-intensity interval training (HIIT) brings about equal or greater benefits that MICT, across age-groups including OA. In OA, HIIT improves aerobic capacity (Robinson, et al., 2017), mechanical efficiency (Jabbour, et al., 2017), glucose tolerance and reduced blood pressure (Izadi, et al. 2018; Lithgow & Leggate, 2018), inflammation in osteo- and rheumatoid arthritis (Keogh, Grigg, & Vertullio, 2018; Bartlett, et al., 2018) , and a reduced risk of falls (Jiménez-García, 2018 ). Reitlo, et al (Reitlo, et al., 2018), in a one-year study in OA (70-77 yr.), showed that adherence to HIIT was consistently higher than MICT in exercise programs involving cycling, resistance exercise, jogging, or swimming.

RT is a popular training method for improving fitness, muscle strength, power, muscle mass, and muscle endurance in OAs. RT is any exercise that causes the muscles to contract against an external resistance. Typically, RT programs emphasize high-load, slow-speed, strengthening exercise. RT in OA using high movement speeds and high external resistance or high movement speeds and low external resistance have demonstrated positive impact on muscle strength, power, muscle mass, muscle endurance, posture, functional tasks related to safety, climbing stairs, recovery when stumbling and tasks such as moving the lower limb to keep from falling ( Jiménez-García, 2018; Steib, Schoene, & Pfeifer, 2010).

Public Health, Environmental, and Policy Interventions

The problem of physical inactivity is universal, so large-scale, population-based strategies are important for intensive individualized and small group interventions (World Health Organization, 2003). Public health, environmental, and policy strategies to enhance physical activity adherence can range from very simple, low-cost interventions to complex policies involving budget allocations and transportation restructuring (Marcus, Owen, Forsyth, Cavill, & Fridinger, 1998; Sallis, Bauman, & Pratt, 1998; World Health Organization, 2003). Mass media educational approaches seem to have little influence on physical activity levels within communities (Marcus et al., 1998). Other types of environmental and policy interventions, however, have shown promising results (Blamey, Mutrie, & Aitchison, 1995; World Health Organization, 2003). These interventions have included posting signs in public areas to encourage the use of stairways, adding bicycle trails, organizing activity clubs and providing additional exercise facilities in the community. While community- and population-based strategies are important for facilitating physical activity, the costs of implementation are often a significant barrier (Brownson et al., 2007; World Health Organization, 2003).

Summary

Exercise adherence in OA is a multifactorial problem encompassing many bio-psychosocial factors. The range of predictors of exercise adherence underscores the need for health services administrators and providers to consider this information in designing strategies to enhance exercise adherence in OA. Exercise programs attendance and adherence are important predictors of health status and wellbeing. Health care professionals should understand the variables influencing adherence to exercise in OA and its consequences on health service delivery and outcomes. Health services administrators and providers should know that low adherence rates will limit the benefits of the exercise program at their facilities. For example, poor attendance and non-adherence are risk factors leading to health service complications in long-term care programs. Administrators of long-term care programs should consider adherence predictors in the projection of expected outcomes, future program needs, and evaluations.

In conclusion, it is imperative that health professionals received training in the conceptual and practical applications of adherence. The literature on exercise adherence in OA is confusing and inconsistent, and few studies measured adherence the same way. Several studies reported high adherence, but adherence was generally higher in supervised programs. Factors associated with greater adherence included higher socioeconomic status, living alone, better health status, better physical ability, better cognitive ability, and fewer depressive symptoms.

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