Falls among the older adult population are costly to the individual, their families, and society. Falls also result in injuries that have both physical and psychological consequences for the older adult. In addition to the loss of mobility experienced as a result of sustaining physical injury, many older adults experience a loss of confidence in their ability to prevent falls and often reduce their physical activity levels in an effort to prevent future falls. Unfortunately, this strategy only reduces their risk in the short-term, eventually leading to physical deconditioning and a further loss of confidence that only serves to increase their risk of falling over the long-term. At a societal level, the economic consequences of falls are substantial, with the direct medical costs of falls within the United States exceeding $19 billion (30). The good news is that up to 42% of falls can be prevented by well-designed exercise programs that are tailored for the level of fall risk and of a sufficiently high dose to significantly lower the total number and/or the rate of falls experienced by older adults (26). In recognition of the important role that exercise plays in preventing falls among older adults, clinical guidelines for fall prevention that have been published in the United States, the United Kingdom, and Australia all include exercise interventions as a recommended strategy for preventing and/or reducing the incidence of falls among older adults (22,25).
THE BENEFITS OF EXERCISE IN REDUCING FALLS
Using a systematic review process, Leslie Gillespie and other fall experts from around the world concluded that exercise, as a stand-alone intervention strategy, is effective in reducing the risk of falling and/or the rate of falling in older adults who are living independently in the community or within retirement communities (11). To arrive at this conclusion, the results of 43 carefully controlled exercise studies were analyzed and synthesized. The authors more fully dissected the content of each exercise intervention using a classification system (15) previously developed by a group of fall experts associated with the Prevention of Falls Network Europe (ProFaNE). Six categories of exercise were subsequently identified. These included 1) gait/balance/functional training; 2) strength/resistance training; 3) flexibility; 4) three-dimensional exercises; 5) general physical activity; and 6) aerobic endurance. Examples of activities included in each identified category are listed in the Table. An “other” category also was created to capture other movement-based strategies that included physical therapy.
Certain Types of Exercise Reduce Falls
The most effective exercise interventions identified were group-based programs that included two or more exercise components, individually tailored programs delivered in the home, and community-based Tai Chi programs. In the case of the group-based exercise programs, the most successful interventions included the components of gait and balance training alone or in combination with a resistance training component. In contrast, stand-alone resistance training programs, whether delivered in a community-based group setting or in the home, did not result in fewer falls. Interventions that involved general physical activity, largely in the form of a walking program, also did not result in fewer falls.
These conclusions are similar to those advanced by Sherrington and colleagues (27) at the University of Sydney who conducted a systematic review of 54 studies that described different types of exercise programs aimed at reducing falls in community-residing older adults. The results of their meta-analysis indicated that falls could be prevented by the delivery of well-designed exercise programs that included progressively more challenging standing balance exercises performed with minimal upper body support, a higher dose of exercise, and no supplementary walking program. Although this latter finding may surprise many reading this article, as it did myself after reading the published study results, Sherrington provided two possible explanations for not recommending the inclusion of a walking component. First, including an unsupervised walking component may expose participants to a greater risk of falling or time is better spent engaging in supervised and tailored balance training versus walking, especially when the program is of a shorter duration. In a more recently updated analysis of exercise programs aimed at reducing falls, Sherrington and her colleagues (26) confirmed their original findings but did indicate that exercise programs, with or without an additional walking component, were effective in reducing falls. The inclusion of moderate to high challenge balance exercises remained important, as did providing a high overall dose of exercise.
Exactly how much exercise is needed before fall rates are significantly reduced? According to Sherrington, a minimum of 50 hours of exercise (i.e., a twice weekly, one-hour program, distributed across a 6-month period) is needed before fall incidence rates are lowered significantly. Although shorter-duration programs (8 to 12 weeks) often produce significant improvements in balance and mobility, it is clear that a higher dose is needed if improving balance and reducing falls are the desired outcomes.
Tai Chi is Effective in Reducing Falls
In addition to its many health benefits, an Eastern form of exercise known as Tai Chi is effective in reducing falls among relatively healthy but sedentary older adults living in the community (16,33). Significant improvements in balance, physical function, fear of falling, and fall rates also have been reported. Successful programs have incorporated more simplified forms of Tai Chi and a smaller number of movement sequences (8 to 24) that emphasize multidirectional weight shifting, multisegmental (arms, trunk, legs) coordinative movements, awareness of body alignment, and synchronized breathing. A gradual reduction in the base of support, increased body and trunk rotation, and reciprocal arm movements also are recommended. Although categorized as a single exercise component according to the ProFaNE classification system, Tai Chi movements, when performed in a standing position, also enhance balance and strength. One particularly successful Tai Chi program that is being disseminated nationally now on the basis of previous research conducted in a controlled setting is Tai Chi: Moving for Better Balance (17). This simplified program includes eight movement forms that are practiced in a group setting usually on a twice-weekly basis for 12 weeks. Despite the success of Tai Chi in reducing falls among older adults at low-to-moderate levels of fall risk, this type of exercise has not been successful in reducing falls in older adults at high-risk for falls (35). It is therefore recommended that older adults be carefully screened before entry into community-based Tai Chi programs to ensure their appropriateness for the program.
Yoga and Pilates: Promising Exercise Interventions?
The fall prevention benefits of two additional forms of exercise have been investigated in recent years in a small number of studies. Similar to Tai Chi, yoga is an eastern form of mind-body exercise that, in its traditional form, combines static poses (asanas) with breathing (pranayama) and meditation. In addition to improving flexibility, balance, and strength, the purpose of yoga is to promote greater relaxation and enhanced mental and emotional well-being. Not only does this type of exercise include exercise components (i.e., balance, strength) that have already proven effective in reducing falls among older adults, it includes relaxation techniques that might prove to be effective in lowering the anxiety and fear that older adults often experience as a result of falling. Unfortunately, little evidence currently exists in support of yoga as an effective exercise intervention for reducing falls (4,6,8,14,25,31). Published studies describing the results of yoga-based interventions currently are limited to small pilot and/or case studies that lack the scientific rigor needed to draw any strong conclusions. The duration of the exercise intervention also has varied widely across studies (e.g., 4 to 12 weeks, daily versus single weekly sessions), no doubt contributing to the mixed findings. More carefully designed randomized controlled studies that are of sufficient intensity and duration are needed before yoga can be recommended as an effective method for preventing falls among older adults.
The effectiveness of Pilates as an exercise intervention for improving balance and strength also has been studied in recent years (1,2,12). This increasingly popular form of exercise combines strength, flexibility, and coordination training with a particular emphasis on strengthening the core muscles of the abdomen, back, and hips. Similar to the yoga research findings, the majority of study outcomes have again been mixed because of poor study designs and/or small sample sizes. More recently, Marie-Louise Bird and her colleagues at the School of Human Life Sciences at the University of Tasmania conducted a more controlled evaluation of a Pilates intervention and its effect on balance and function in a group of 27 community-residing older adults (aged >60 years). Although the investigators did not measure the intervention’s effect on actual fall incidence rates, they did include other measures of fall risk (e.g., static and dynamic balance and lower-body strength). Improvements in multiple static and dynamic measures but not lower-body strength were observed after the 5-week intervention.
The Effectiveness of Dance-Based Interventions
A small number of studies (13) have explored the effectiveness of such dance forms as the Argentine tango (18), traditional and social dances (7,29,33), and dance-based aerobics (28,34) on reducing falls in community-residing older adults as well as select clinical populations (e.g., Parkinson’s disease). There are many factors that make dance-based interventions attractive as an intervention strategy for increasing physical activity levels and reducing falls among older adults. Merom and colleagues (20) note that variety is intrinsic to dance (e.g., styles, type of music, and steps) and therefore less likely to become boring for older adults. Dropout rates from dance classes also have been shown to be significantly lower (10%) than Tai Chi (23%) and other exercise programs (26% to 49%) designed for older adults (e.g., cardio, strength, disease-specific) (10,19). The higher adherence rates to dance classes will, in turn, provide the dose of exercise Sherrington recommends is needed for reducing fall incidence rates in a larger number of older adults. Cross-sectional studies also have shown that older adults who dance have superior balance and gait characteristics compared with their peers (32,36), further suggesting that this type of exercise programming has strong potential as a fall prevention intervention. Although the results of some studies have demonstrated improvements in static and dynamic balance, as well as other indices of fall risk, none of the intervention studies, whether randomized controlled trials or quasi-experimental studies, investigated whether these programs also reduced the incidence of falls. The good news is that a group of researchers in Australia currently is investigating whether a community-based social dancing intervention can reduce fall incidence rates as well as improve cognitive function in a large group of older adults (N = 450) residing in self-care retirement villages using a randomized controlled trial design (20).
Changing Behavior is Important for Long-term Exercise Adherence
Because long-term adherence to exercise can be quite low, it is important to not only provide older adults with a choice of different exercise programs that best match their physical capabilities and physical activity interests but also incorporate strategies during the program that are aimed at improving the older adult’s desire to continue exercising even after a structured program ends. Effective strategies include providing refresher sessions, ongoing self-monitoring in the form of exercise diaries or logs, and in-person or phone contact aimed at assisting the older adult overcome barriers to exercising that may arise. Too often, we assume that simply having older adults participate in well-designed exercise programs is sufficient to change their behavior and attitudes toward exercising permanently. Unfortunately, this is true for only a small percentage of older adults who are in the more advanced stages of behavior change and exhibit higher levels of task, maintenance/barrier, and recovery self-efficacy. According to Wendy M. Rodgers from the University of Alberta, not only is it important that our older adult clients believe in their ability to perform successfully the exercises we will ask them to perform during an exercise program (i.e., task self-efficacy) but it also is important that they believe in their ability to overcome problems or barriers that often arise during and after an exercise program ends (i.e., maintenance/barrier self-efficacy) and/or resume exercising after a disruption — perhaps because of illness or injury (i.e., recovery self-efficacy). Although some participants already may demonstrate high levels of each of these different types of self-efficacy, others will need to develop their abilities as the program progresses (23). Being aware of the role each of these different types of self-efficacy plays in shaping the older adult’s involvement in and long-term adherence to exercise and then being intentional in our approach to helping program participants develop these abilities will be integral to the program’s success.
BEST PRACTICE RECOMMENDATIONS
A number of recommendations can be made based on the many published studies that have investigated the benefits of different types of exercise in reducing falls among older adults. Based on her most recent review of different exercise interventions, Sherrington and colleagues (26) have developed a set of best practice recommendations that practitioners can use to guide them when developing exercise programs designed to prevent falls. Important best practice recommendations she identifies include the following:
- Provide group-based or in-home programs that include moderate-to-high challenge balance exercises and are of a sufficient duration and intensity to lower fall incidence rates significantly;
- Add a resistance exercise component because it may yield other important long-term benefits;
- Include a supplementary walking program if the time spent in a supervised exercise environment remains high;
- Learn about other risk factors for falls (e.g., vision, use of psychoactive medications, cognition) so you can refer older adults to their primary care physician for further evaluation;
- Develop different types of exercise programs that are ongoing so that the benefits are not lost across time.
I would add to this last recommendation the need for exercise professionals to become skilled in behavioral counseling and include strategies designed to foster long-term changes in their clients’ behaviors and attitudes toward preventing falls (3). Although ideal, it is not always going to be possible to provide an ongoing and structured exercise program in some settings. As such, it is important to assist the older adult with developing high levels of task, barrier, and recovery self-efficacy, as well as strong self-management skills during the program.
The Type and Intensity of Exercise Should Vary According to the Level of Fall Risk
Although we certainly do not have all the answers at this time, I offer the following recommendations as a starting point for designing physical activity or exercise programs for older adults at different levels of fall risk. For older adults at a low risk for falls (i.e., no history of falls in the previous year, absence of known risk factors for falls), a variety of different physical activity and exercise options should be made available. These options also should be based on their exercise interests and preference for setting (e.g., group or in-home). Guidelines jointly published by the American College of Sports Medicine and the American Heart Association in 2007 recommend that a minimum of 30 minutes of moderate-intensity aerobic physical activity on 5 days each week or 20 minutes of vigorous-intensity aerobic activity on 3 days each week is necessary for the promotion and maintenance of health. Performing 8 to 10 strength/resistance training exercises at a moderate to high level of intensity is also recommended. The chosen exercises should target the major muscle groups and be performed at least two or more nonconsecutive days per week. Finally, engaging in flexibility exercises for at least 10 minutes on 2 days per week also is encouraged (21). Although, in the 2007 guidelines, the inclusion of balance exercises was recommended only for those older adults considered to be at an elevated risk of falling, they have been included in a more recent position stand addressing the quantity and type of exercise needed for apparently healthy adults of all ages to maintain cardiorespiratory, musculoskeletal, and neuromotor fitness (9). Additional benefits of engaging in neuromotor exercise training a minimum of 2 to 3 days per week for 20 to 30 minutes include a reduction in fear of falling and likely the number of falls experienced by older adults. In light of the fact that having good balance is a prerequisite for participation in a wide range of recreational and sporting activities, including a balance and agility component into an exercise program designed for older adults at all levels of function and fall risk is warranted. At the Center for Successful Aging, for example, in each of our multicomponent group exercise classes, at least 10 to 20 minutes of each 90-minute class is devoted to improving the balance, agility, and motor coordination of our high-functioning older adult clients. For those clients identified with balance and mobility disorders, more intensive fall risk reduction classes are available (24). One additional benefit of group-based classes is that they provide a socially supportive activity environment and a level of supervision and structure that many older adults need to develop high levels of task self-efficacy. The overarching goal is to foster a desire to continue exercising for the long-term.
Other recreational activities that incorporate many of the important functional parameters listed above include tennis, golf (combined with walking versus riding around the course), bicycle riding, and different types of dancing to music (e.g., ballroom, line dancing, tango). As discussed earlier in this article, Tai Chi also has been shown to be effective in reducing fall incidence rates among relatively healthy community-residing older adults.
For older adults identified at a moderate risk for falls (i.e., history of one to two falls in the previous year, presence of one or more known risk factors for falls, including comorbid medical conditions), regularly engaging in physical activity can slow the progression of disease and/or system impairments that limit their ability to perform many daily activities independently. Collectively, research findings suggest that this group of older adults will derive more benefit from participating in structured exercise programs that systematically target the physical risk factors associated with falls (e.g., muscle weakness, gait and balance impairments). As noted earlier, the published American College of Sports Medicine exercise guidelines also recommend including balance training in any exercise program designed for older adults who are identified at risk for falls (21). Specific recommendations include introducing progressively more difficult balance activities that reduce the base of support (e.g., semitandem, tandem, one-legged stance positions), involve more dynamic movements aimed at improving center-of-gravity control, manipulating the amount of sensory information available (e.g., eyes closed), and strengthening the muscle groups that contribute to postural control (i.e., ankle, knee, hip) (24,26,27). Performing more advanced balance activities that require greater cognitive effort (e.g., dual-task activities) also will have a positive influence on essential cognitive processes (e.g., attention, memory, problem solving). Observable improvements in balance and mobility also positively influence the individual’s level of self-confidence and more global fear of falling. Whether this type of program is implemented in a group-structured setting or as a home-exercise program does not seem to influence the outcomes. A significant reduction in fall risk and/or fall incidence rates has been shown in both types of settings.
Individually prescribed exercise programs, such as the Otago Home Exercise Program (5), also seem to be most effective for frail older adults who are advanced in age (>80 years) and/or at high risk for falls. Older adults at high risk for falls are likely to have sustained an injury-related fall within the past 6 months, present with two or more risk factors associated with falls, and have comorbid conditions that are less medically stable. Health care professionals (e.g., physical therapists, nurses) who are skilled in selecting the type of exercise based on the specific needs and abilities of the individual, as well as progressing the difficulty level of the various exercise components, are best suited to leading these types of programs.
The initial focus in these types of exercise programs should be on strengthening all major muscle groups in a seated or supported standing position until sufficient strength permits the inclusion of minimal or unsupported standing exercises that emphasize dynamic balance and mobility. The overarching goal of these individually prescribed programs is to raise the older adult’s physical capacity to a level that will allow for greater independence in the performance of essential activities of daily living (i.e., dressing, bathing, transfers) and require less assistance with more advanced activities of daily living (e.g., shopping, walking in the community, assorted household chores).
Although beneficial, exercise alone is unlikely to be sufficient to reduce fall incidence rates in older adults at high risk for falls. In addition to a carefully designed exercise program, these older adults will derive greater benefit from an intervention strategy that begins with a comprehensive medical screening to identify the specific fall risk factors contributing to their heightened fall risk. Subsequent intervention strategies may include such things as treatment of chronic medical conditions, physical therapy, vision and/or hearing assessments, medication review, training in assistive-device use, home assessment and modification, and counseling aimed at changing fall risk behaviors.
A review of the fall prevention literature, combined with my own professional experience working with older adults at risk for falls, confirms my opinion that carefully designed exercise programs substantially can reduce falls among older adults. Effective programs are distinguished by the following characteristics: they include static and dynamic balance activities tailored to the risk level of the older adult; the balance exercises are made progressively more challenging across time; the exercises are performed with minimal support; a functional resistance training component is included and also is progressed across time. Finally, effective programs will purposefully include strategies aimed at fostering long-term changes in the older adult’s behaviors and attitudes toward preventing falls.
BRIDGING THE GAP
Exercise, as a stand-alone intervention strategy, is effective in reducing falls among older adults. But which types of exercise are most effective and what are the key components of successful fall prevention programs? This review article will address each one of these questions and share best practice recommendations emerging from more than two decades of fall prevention research.
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