CEU Corner: Working With Older Adults

This issues CEU Corner and Quiz Feature is Working with Older Adults: Health Challenges That Exercise Can Help

by Jan Schroeder, PhD

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Taking on clients aged 65 and older can do more than expand your client base. Research shows it provides life-changing rewards—for both clients and fitness professionals.

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Have you noticed an increase in the number of older adults you’re training or leading in your group ex classes? Currently, older adults (aged 55 and older) are the largest population frequenting our fitness facilities (Schroeder & Donlin 2013). One reason is the “graying of America,” which refers to older adults being the fastest-growing segment of our population. Another reason is that the health benefits of exercise, which can include staying independent, are becoming better known to older individuals, who, in turn, are making it part of their lifestyle.

For personal trainers and group exercise instructors alike, an increase in client numbers in any population can be a boon to business. However, training this age group requires special knowledge, care, modifications and safety considerations, as older adults are likely to have more health issues than younger adults.

In this article, we will review several common health concerns of this age group—frailty and sarcopenia, osteoporosis, cardiovascular disease, type 2 diabetes, and Alzheimer’s disease—and how regular exercise affects their progression. When working with older adults, it is important to be aware of the multiple challenges you may encounter, so you can adjust your programming to provide a workout that is safe, effective and enjoyable.

Muscle Health & Sarcopenia

Sarcopenia, defined as loss of muscle mass and function, is considered one of the causes of frailty in older adults. In Clegg et al. (2013), frailty is said to exist when multiple physiological systems weaken, making it more difficult for the body to return to homeostasis after a stressor event; however, there is no one agreed-upon definition of frailty (see “Frailty and the Older Adult”).

Beginning as early as the fourth decade of life, skeletal muscle mass and strength begin to decline in a linear manner, with up to 50% of mass being lost by the eighth decade of life (Metter et al. 1997).

THE DEVELOPMENT OF SARCOPENIA

The changes associated with sarcopenia are characterized by overall declines in the size and number of skeletal muscle fibers—mainly the fast-twitch (type II) muscle fibers—and a noticeable infiltration of fibrous and adipose tissue into the muscle (Lexell 1995). In addition, there is a reduction in the number of satellite cells, which begin the process of muscle repair and regeneration in response to heavy muscle use or injury; this is also most prevalent in type II muscle fibers (Snijders, Verdijk & van Loon 2009). All of these changes lead to declines in the muscular system’s strength, mass and function.

The consequences of worsening sarcopenia can be quite severe, including such adverse health outcomes as increased insulin resistance, falls, fatigue and even death (Peng et al. 2012; Newman et al. 2006; Landi et al. 2012).

EXERCISE FOR MUSCLE STRENGTH AND FUNCTION

Among older adults, most sarcopenia interventions have focused on improving environmental causes, namely through boosting physical activity levels and providing adequate nutrition.

Resistance training effectively increases strength in older persons with sarcopenia and frailty (Landi et al. 2014). Through mechanical loading (via strength and/or aerobic exercise), we find improvements in muscle protein synthesis, increases in myofibrillar protein through activation of satellite cells, and decreases in fat infiltration into muscle (Timmerman et al. 2012; Aagaard et al. 2010). Together, these benefits allow older adults to show improved outcomes for mobility and functional ability (de Vries et al. 2012; Theou et al. 2011).

Power training has proved to be more effective for enhancing physical function in older adults than conventional slow-velocity training (Miszko et al. 2003). While power training may not be the starting point for most clients, it does improve gait speed and performance of functional tasks such as standing up from a chair and climbing stairs (Bassey et al.1992; Beijersbergen et al. 2013). Moreover, power training specifically targets the type IIb muscle fibers, which are the ones most affected by age-related atrophy (Lexell 1995).

Editor’s note: For more on this, read “Speed, Agility and Quickness for Adult Clients” in the Summer issue. To read more about research on slow resistance training, read this issue’s Q+A column.

EXERCISE SAFETY WITH FRAILTY AND SARCOPENIA

Fitness professionals should be aware of exercises that may increase the risk of falling in frail older adults. Due to lack of strength, these clients may have trouble with toe clearance when walking; therefore, it may be best to start them with seated exercises. Also, balance may be compromised, so machine weights are recommended for resistance exercises.

Bone Health & Osteoporosis

Osteoporosis is defined as porous bone, which occurs when the body loses too much bone, does not produce enough bone, or experiences a combination of these.

Currently, about 10 million U.S. women and men have osteoporosis, and another 44 million have low bone density (osteopenia), placing them at increased risk of the disease. Studies suggest that 1 in 2 women and 1 in 4 men over the age of 50 will break a bone because of osteoporosis (NOF 2018).

THE DEVELOPMENT OF OSTEOPOROSIS

Bone is a dynamic tissue that is continually being remodeled in the adult body through the work of osteoblasts, bone cells responsible for bone formation, and osteoclasts, cells that “oversee” bone resorption, or breakdown. Osteoblasts lay down (deposit) a matrix of collagen and calcium phosphate to allow bone to be flexible yet strong, so it can withstand external forces.

Earlier in life, bone formation surpasses resorption, helping to build strong, dense bones up until the age of peak bone mass (around 30 years). Following peak bone mass, resorption gradually overtakes formation, and this process is accelerated for women during the menopausal transition. Osteoporosis is more likely to occur in a man or woman who did not reach optimal peak bone mass.

If we take a close look at bone, it has a honeycomb appearance. When osteoporosis occurs, the holes in the honeycomb become larger and the bone becomes less dense. As bone gets more porous, it becomes more fragile, making it susceptible to fractures from falls or even a hug. The hip, spine and wrist are the most common sites of osteoporotic fractures, but other bones can be affected as well.

EXERCISE FOR BONE HEALTH

Exercise is recommended to prevent and treat osteoporosis, as bone is responsive to mechanical loading, both through muscle forces and through ground reaction forces (Yokota, Leong & Sun 2011). While the exact exercise design needed to stimulate optimal skeletal adaptations has yet to be determined, we do know that the effects of exercise on bone depend on modality, dose and intensity.

Research suggests that not all exercise is equal when it comes to improving bone health. For example, while walking is a wonderful exercise for aerobic fitness, cardiometabolic factors and weight loss, a meta-analysis revealed minimal or no effect on bone in peri- and postmenopausal women who walked regularly (Ma, Wu & He 2013). In addition, as mentioned earlier, walking can pose a fall risk for older adults with frailty, which can further increase fracture risk.

It is important to note that it is never too late to start a bone-protecting program, as exercise training may prevent fractures even when started after menopause (Kemmler et al. 2015). Exercise modes found to promote bone growth include certain forms of weight-bearing impact exercise and resistance training.

Research has shown enhanced bone production in older adults who participated in exercise that involved moderate- to high-impact weight-bearing moves (loads that were more than double the person’s body weight) and was applied in a progressive, novel and multidirectional way (Vainionpaa et al. 2006; Allison et al. 2013). To achieve maximum benefit from resistance training, the activity should be progressively increased over time, have a high magnitude of loading (~80%–85% of one-repetition maximum) and be performed at least twice per week (Zhao, Zhao, & Xu 2015; Kerr et al. 1996).

EXERCISE SAFETY WITH OSTEOPOROSIS

While the previously mentioned exercise modalities have proven effective at building bone, that does not mean they are always safe for older adults who have already been diagnosed with osteopenia or osteoporosis. For individuals with osteoporosis, exercise precautions include avoiding loaded forward flexion and rotation of the spine. Activities that carry an increased risk of falling should be avoided or used with extreme caution. Exercises that require sudden, forceful movement should also be avoided unless introduced gradually as part of a progressive program.

Cardiovascular Health & CVD

Cardiovascular disease (CVD) is the number-one killer of men and women over the age of 65 in the United States. More than 1 in 3 American adults have one or more types of CVD. Of these individuals, 46.7 million are estimated to be 60 years of age or older (AHA 2017b).

THE DEVELOPMENT OF CVD

There are many types of cardiovascular disease, which can be defined as conditions that affect the structure or function of the heart and blood vessels. A few of the most common types of CVD include coronary artery disease (narrowing of the arteries in the heart), myocardial infarction (heart attack), stroke (a blocked or burst blood vessel in the brain), and arrhythmias (abnormal heart rhythms).

The causes of each type of CVD differ, but the most common are atherosclerosis (fatty deposits in the arteries) and damage to the circulatory system as a result of another health condition, such as diabetes and hypertension (high blood pressure).

Atherosclerosis occurs when fatty deposits, or plaque, accumulate in the arteries. Plaque is a waxy substance made up of cholesterol, fatty molecules and minerals. The progressive buildup of plaque thickens and stiffens artery walls, and this can impede blood flow to organs and tissues, including the heart, thereby inhibiting delivery of vital nutrients and oxygen.

Hypertension, hyperlipidemia (a high level of blood fats), diabetes, smoking, obesity, physical inactivity and poor nutritional habits all contribute to an increased risk of developing CVD.

EXERCISE FOR CARDIOVASCULAR HEALTH

The benefits of exercise training on CVD have been known since the 1950s, when Morris and Crawford (1958) found lower rates of coronary heart disease among people with active occupations versus sedentary jobs. Consistent training improves the CVD risk profile by lowering blood pressure, reducing triglycerides and increasing HDL (good) cholesterol, improving glucose metabolism and insulin sensitivity, and decreasing body weight (Whelton et al. 2002; Mann, Beedie & Jimenez 2014; Thomas, Elliott & Naughton 2006).

Additional improvements in risk profiles may result from enhanced vagal tone (a biological process that refers to activity of the vagus nerve), leading to lower heart rates; vascular remodeling, including enlargement of blood vessel diameters; and improved endothelial function (Beere, Glagov & Zarins 1992; Joyner & Green 2009). The American Heart Association (2017a) suggests that to improve overall cardiovascular health, one should participate in at least 150 minutes per week of moderate exercise or 75 minutes per week of vigorous exercise (or a combination of moderate and vigorous activity). These recommendations stem from research indicating that CVD mortality gradually declines with increasing levels of moderate-intensity physical activity; interestingly, vigorous intensity affords no additional benefits over moderate intensity (Wen et al. 2011; Lee et al. 2014).

Adding strength training to aerobic programs is also recommended, as research has shown that this combination tends to produce larger increases in cardiopulmonary fitness and improvements in quality of life for individuals with CVD (Marzolini, Oh & Brooks 2012).

EXERCISE SAFETY WITH CARDIOVASCULAR DISEASE

If clients experience chest pressure or pain in the chest, neck, arm, jaw or shoulder, immediately stop exercising and call 911. Exercise should also be halted if a client with CVD becomes overly fatigued or experiences unusual shortness of breath.

Clients with hypertension should monitor their blood pressure before, during and after exercise. Exercise should stop immediately if their blood pressure reaches approximately 240/115 mm HG.

When clients perform resistance training, they should avoid significant isometric segments, as these may trigger a dramatic rise in blood pressure. Clients taking antihypertensive medications should transition slowly when getting up from the floor because they will be more susceptible to orthostatic hypotension, a rapid drop in blood pressure that can happen when a person moves quickly from a seated/supine position to standing.

Blood Sugar & Type 2 Diabetes

The incidence of diabetes has been steadily increasing in the United States, and currently more than 100 million individuals have either diabetes or prediabetes. Older adults are at greatest risk, with an estimated 25% of people over age 65 having diabetes and an additional 48% having prediabetes. The majority of cases (90%–95%) are type 2 diabetes (CDC 2017).

THE DEVELOPMENT OF TYPE 2 DIABETES

Diabetes is a metabolic disorder that impairs the body’s ability to either produce or effectively use insulin, a key hormone for moving glucose from the bloodstream to the body’s cells. When everything is working as it should, the pancreas produces enough insulin (but not too much), and the hormone effectively facilitates the movement of glucose into the cells, where it is used to create energy.

Insulin resistance happens when defects in the insulin receptors on the body’s cells fail to unlock the cells to allow glucose to enter, resulting in a buildup of glucose in the bloodstream. This causes the pancreas to produce more and more insulin to try and move the glucose into the cells. After a while, the islet cells of the pancreas (which produce the insulin) become overworked, and insulin production slows, resulting in an increase in glucose in the bloodstream.

Older adults are at high risk of developing type 2 diabetes, owing to the combined effects of insulin resistance and compromised pancreatic function. Age-related insulin resistance appears to be associated primarily with obesity, sarcopenia and physical inactivity (Amati et al. 2009).

Note: In type 1 diabetes, which accounts for only about 5% of all diabetes cases, the insulin-making cells in the pancreas have been destroyed, so insulin therapy must be used every day. Type 1 has different causes from type 2 and is generally not associated with obesity or inactivity. Fitness professionals working with people who have type 1 diabetes should strive to learn more about this very different form of the condition.

EXERCISE FOR BETTER BLOOD SUGAR

Along with medication and nutrition, exercise has long been a foundational practice in the treatment of type 2 diabetes. Research has shown that both aerobic activity and resistance training are effective in lowering weight, which in turn reduces insulin resistance (Ross et al. 2000).

Exercise reduces blood sugar levels by assisting glucose uptake by skeletal muscles via the glucose transport protein called GLUT4. In type 2 diabetes, deficiencies in the insulin receptors impair glucose uptake and GLUT4 translocation. Regular exercise can help combat insulin deficiencies by improving GLUT4 translocation.

This benefit can be seen in research conducted by DiPietro et al. (2013), who observed a greater improvement in blood glucose on days when older adults with diabetes walked for 15 minutes after each meal (breakfast, lunch and dinner, total 45 minutes) than on days when they walked for 45 minutes consecutively. In fact, in 2016, the American Diabetes Association updated its guidelines for physical activity and exercise for people with diabetes, recommending less overall sedentary time every day; the most notable change calls for 3 or more minutes of light activity every 30 minutes during prolonged sedentary periods (ADA 2016).

EXERCISE SAFETY WITH TYPE 2 DIABETES

Older adults with diabetes should be encouraged to participate in aerobic, strength, flexibility and balance activities. If individuals have type 2 diabetes, they are most likely overweight and sedentary; therefore, their program should start slowly and progress slowly.

It is important for older adults with diabetes to track their blood glucose levels before, during and after exercise, to avoid hypoglycemia (a dangerous drop in blood sugar). Clients should have a quickly absorbable carbohydrate on hand to provide glucose to the bloodstream in case of hypoglycemia.

To prevent hypoglycemia, a client who injects insulin should avoid exercising when the effect of the insulin injection is peaking. Time to peak action is determined by the type of insulin used; therefore, it is important to discuss the drug’s action with the client to determine the best time to exercise. Other safety concerns may include exercising in extreme hot or cold if the client experiences autonomic neuropathy (which affects the body’s ability to regulate temperature), and strenuous upper-extremity exercise if the client is at risk for retinopathy (nerve damage to the eyes). Because many people with type 2 diabetes develop peripheral neuropathy (nerve damage to the extremities), clients should talk with their doctor about how to prevent and treat foot ulcers and other foot problems.

Brain Health & Alzheimer’s Disease

Alzheimer’s disease is the most common form of dementia, a progressive and irre­versible neurodegenerative disease. It is estimated that 5.7 million Americans are living with Alzheimer’s disease, and 96% of them are over the age of 65 years. This disease is the fifth leading cause of death in older adults (AA 2018).

THE DEVELOPMENT OF ALZHEIMER’S DISEASE

Researchers are working to understand the brain changes involved in the onset and progression of Alzheimer’s disease. These changes may start to occur decades before symptoms like memory loss appear (AA 2018; NIA 2018a). Cognitive symptoms—such as confusion, disorientation, and impairments to memory, thinking and language—usually develop slowly, gradually worsening over time (NIA 2018a).

One of the first things that occur in the development of Alzheimer’s disease is a progressive loss of neurons (specialized cells that process and transmit information via chemical and electrical signals) in certain areas of the brain, such as the entorhinal cortex and the hippocampus, both of which support memory. As the disease progresses, neurons are also lost within the cerebral cortex, which is responsible for language, reasoning and social behavior (NIA 2018b). Hallmark signs of Alzheimer’s disease—and the prime suspects in cell death and brain tissue loss—are accumulations of amyloid plaques and neurofibrillary tangles.

Amyloid plaques form when pieces of the protein beta-amyloid bunch together between neurons. These bunches may block cell-to-cell communication and prompt the immune system to trigger an inflammatory response.

Neurofibrillary tangles are abnormal accumulations of a protein called tau that collect inside neurons. Tau forms part of a structure called a microtubule within the neuron. In a healthy brain, the microtubule helps to transport nutrients and other important substances from one part of the nerve cell to another. In the brain affected by Alzheimer’s disease, there is an abnormal chemical change in tau that causes it to detach from the microtubule and stick to other tau molecules, forming tangles within the neuron. As a result, the microtubule structures collapse, disrupting communication between neurons and leading to cell death (Binder et al. 2005).

Researchers are also interested in the inflammatory response and its link to Alzheimer’s disease. Microglial cells are key cells of the immune system in the brain. These cells, along with astrocytes (another type of glial cell), play the role of cerebral macrophages, which means they surround and kill harmful microorganisms, ingest foreign material, remove dead cells and boost immune responses. In Alzheimer’s disease, microglia and astrocytes fail to do their job; they accumulate around neurons, releasing chemicals that kill the neurons or cause chronic inflammation and further damage (Blasko et al. 2004).

All of these structural changes within the brain lead to functional deviations. During the early stages of Alzheimer’s, individuals may experience issues with memory or concentration. As more damage occurs in the brain, they may enter the longest stage of the disease—the middle stage—and have difficulty expressing thoughts and completing routine tasks. In the final stage, people lose the ability to respond to their surroundings, to carry on a conversation and, ultimately, to control movement (NIA 2018a).

EXERCISE FOR BRAIN HEALTH

From research, we understand that the risk for brain dysfunction and Alzheimer’s disease is increased by obesity, diabetes, hypertension, hypercholesterolemia and chronic inflammation (Morris et al. 2014). We also know that exercise helps to control these conditions, while reducing the risk of Alzheimer’s disease (Scarmeas et al. 2009).

Alzheimer’s disease researchers are still working to determine exactly how exercise affects the brain. Animal studies have shown aerobic exercise to be a promising approach for counteracting hippocampal damage and cognitive deficits caused by Alzheimer’s disease. Exercise appears to stimulate growth factors that promote neurogenesis, the formation of new neurons (Intlekofer & Cotman 2013).

Most of the research supporting a relationship between exercise and brain health has looked at aerobic exercise. A recent meta-analysis of 19 research studies on humans determined that aerobic exercise training may postpone the decline in cognitive function that occurs in individuals who are at risk of or have Alzheimer’s disease (Panza et al. 2018).

Little data exists on the role of resistance exercise in promoting brain health; however, a few studies do show promising results. Liu-Ambrose et al. (2010) found that resistance training benefited the executive cognitive functions of selective attention and conflict resolution among older women. Nagamatsu et al. (2012) found that resistance training was associated with modest cognitive benefits in study participants with cognitive impairment. That said, much more research is needed in this area before the appropriate resistance exercise design for individuals with Alzheimer’s disease can be determined.

Little data exists on the role of resistance exercise in promoting brain health; however, a few studies do show promising results. Liu-Ambrose et al. (2010) found that resistance training benefited the executive cognitive functions of selective attention and conflict resolution among older women. Nagamatsu et al. (2012) found that resistance training was associated with modest cognitive benefits in study participants with cognitive impairment. That said, much more research is needed in this area before the appropriate resistance exercise design for individuals with Alzheimer’s disease can be determined.

EXERCISE SAFETY WITH ALZHEIMER’S DISEASE

When working with a client who has Alzheimer’s disease, the focus should be on aerobic-type activities that are familiar to the individual. The program should start off slowly and progress slowly. Fitness professionals should keep in mind that what clients can accomplish on one day may be very different from what they can accomplish on another day.

Since these clients may have difficulty with balance, owing to changes in visual per­ception and coordination, adding in neuromotor control activities is suggested. The workout area needs to be clutter-free and well-lit, with minimal peripheral movement and noise, as these can be disconcerting to the clients.

Any new skills, such as resistance training, will require specific instructions and repetition. Cues should communicate only one instruction at a time. Machine weights are safer than free weights, because the latter can be dropped.

The Rewards of Training Older Clients

Specific exercise recommendations for each older adult client will depend on his or her baseline fitness and existing comorbidities. It is therefore vital to perform an initial assessment and then assess often on an ongoing basis.

Individual clients may have multiple physical limitations and/or comorbidities. Fitness professionals should ensure that, after a client is cleared to exercise, the healthcare team continues to provide specific input to help with adjusting the training program as needed.

While these factors may add a challenge to working with older adults, the benefits are proven, positive and rewarding. Fitness programming can enhance functional and cognitive abilities, increase glucose control, reduce CVD risk, and possibly stabilize bone loss. If improving others’ quality of life is among your most compelling career objectives, this demographic may be a perfect fit for you.

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Meet our experts

AFM_Authur_Schroeder JAN SCHROEDER, PHD,, is chair of the Department of Kinesiology at Long Beach State University, where she teaches fitness. She has written more than 60 articles on exercise physiology/fitness and teaches group exercise as an AFAA-certified instructor.

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