Health promotion is an important issue worldwide. Many scholars from various disciplines have devoted time and effort to developing and applying various procedures to promote health in people of all ages. Older adults are a fast-growing segment of the population, and their special needs resulting from declining physical functions should be taken into account when selecting appropriate activities to promote health. More importantly, activities selected need to be incorporated into older adults' daily life in order to enhance well-being and quality of life. Such, in turn, could lead to decreases in healthcare resource consumption and healthcare dollar expenditures required to take care of this elderly population. Research studies support the conclusion that exercise is a recommended behavior to prevent, delay, and manage many chronic illnesses in older adults (Clark, 1996). The silver yoga exercise program, which is a type of mind-body exercise specific-tailored to older adults, is a therapeutic-based exercise choice for older adults.
Yoga means union or joining together of the body and mind of an individual with the universal spirit (Stanescu, Nemery, Veriter, & Marechal, 1981). The goal of yoga therapy is to promote health and self-awareness (Feuerstein, 2000). Studies have supported yoga's potential benefits to the reduction of body mass index values, low-density lipoprotein cholesterol, fibrinogen, and blood pressure (Damodaran et al., 2002). Through static physical postures, yoga uses stretching to improve muscular strength and flexibility (Chen & Gan, 1997) that can benefit the management of low-back-related pain (Hill, 2004). In particular, yoga has been useful in treating various forms of arthritis (Dash & Telles, 2001; Garfinkel & Schumacher, 2000) and reducing the severity of muscular-skeletal disease (Garfinkel & Schumacher, 2000). Furthermore, studies of yoga-based interventions conducted with healthy populations have shown that these interventions help decrease depression and anxiety (Waelde & Thompson, 2004), decrease sleep disturbances, improve sleep quality (Cohen, Warneke, Fouladi, Rodriguez, & Chaoul-Reich, 2004), and improve perceived self-efficacy (Waelde & Thompson, 2004).
To accommodate the reduced body flexibility experienced by many older adults, a safe and manageable yoga program specifically-tailored for older adults was developed and named “silver yoga” (Chen, Tseng, Ting, & Huang, 2007). The term “silver” represents the gray hair of older adults and reflects the wisdom that older people have accumulated from their rich life experiences. The silver yoga program includes four phases: (1) warm-up: eight postures to loosen up the body structure; (2) hatha yoga: seven gentle stretching postures to increase range of motion and progressive muscle relaxation in older adults with special consideration for their physical abilities and tolerance; (3) relaxation: three activities to rest the body; and (4) guided-imagery meditation: two imagery-guided activities to facilitate a state of relaxation. Abdominal breathing is emphasized in each phase of the program, and the postures in the silver yoga program are considered less strenuous than those used in traditional yoga (Chen, Tseng, et al., 2007).
The silver yoga program has been critically reviewed by 10 experts with expertise in yoga, elderly exercise, geriatric nursing, geriatric physical therapy, osteopathy, sports physiology, sports medicine, and/or sports injuries (Chen, Tseng, et al., 2007). A pilot-testing of silver yoga effects is essential before the program is introduced and promoted to older adults. The purpose of this study was to establish preliminary evidence for the health promotion effects of the silver yoga program in older adults.
A one-group, pre-post tests pilot study design was used. The health outcomes of participants were measured at two points in time: the baseline and upon conclusion of the four-week silver yoga intervention.
Setting and Participants
The study was conducted at a senior activity center, southern Taiwan. A convenience sample of 16 female participants was recruited, of whom 14 completed the study (retention rate: 87.5%). One participant withdrew due to a family vacation and the other due to family issues (e.g., the death of her mother). Inclusion criteria for participants included: (1) community-dwelling seniors aged 60 and over, (2) no previous training in any form of yoga, (3) able to walk without assistance, (4) cognitively alert as demonstrated by a Short Portable Mental Status Questionnaire (SPMSQ) score of eight or higher (Pfeiffer, 1975), and (5) “independent” or “mildly-dependent” in self-care as indicated by a Barthel Index (BI) score of 91 or higher (Mahoney & Barthel, 1965). Due to both the self-reporting format and the nature of yoga activity, participants with dementia, confined to wheelchairs, or with severe or acute cardiovascular, musculoskeletal, or pulmonary illnesses were excluded from the study.
The intervention of this study, the silver yoga exercise program, was implemented as a group exercise by a certified yoga instructor who had prior experience training older adults in yoga. Based on previous study experiences with elderly populations (Chen, Lin, et al., in press), the frequency of the silver yoga intervention was set at three practice sessions per week (70 minutes per session) for four weeks. To prevent harm to participants from their exercises, a RN-licensed research assistant was present during all of the sessions. The certified yoga instructor led the group silver yoga practice and the RN-licensed research assistant took attendance and watched over the safety of participants during practice sessions. The four phases of the silver yoga program, including warm-up, hatha yoga, relaxation, and guided-imagery meditation, were implemented in each 70-minute intervention session.
The average attendance rate was 91.07%, with the most frequently noted reasons for absence including scheduling conflicts with volunteer works (30%), family business, such as adult children's visits (30%), and physical discomfort due to flu (20%). Although the research assistant was required to record any sign or symptoms of discomfort occurring during a yoga session, no incidence of such occurred. Due to the preliminary testing of the silver yoga program, participants were encouraged to practice only with the group when the certified instructor and the RN-licensed research assistant were present. However, due to the ethical concern of not being able to forbid the participants to practice privately, a self-practice log was provided for participants to record the amount of time spent in self-practice at home. No participant self-practice was reported and no additional exercise activities were executed during the study period.
Health outcome measurements included the physical health (physical fitness and physical health self-actualization) and psychological health (sleep quality, depression state, and mental health self-actualization) of participants. Physical fitness was further defined to include body composition, cardiovascular-respiratory fitness, hand-grip strength, lower body flexibility, lower limb muscle endurance, balance, and range of motion. An RN-licensed researcher was trained to follow standardized procedures to collect data in order to measure participant health outcomes.
Body composition included body height, body weight, body mass index (BMI), and body fat percentage. Body height was measured in centimeters using a tape measure and a set square while the subjects were standing straight against a wall without shoes or socks. Body weight was measured in kilograms using a digital scale on a flat floor, with participants wearing light clothing only and no shoes or socks. BMI was calculated using body weight (in kilograms) divided by body height squared (in meters). Body fat percentage was calculated using a digital body fat scale (TANITA - TBF521).
Cardiovascular-respiratory fitness included breathholding duration, lung capacity, and blood pressure at rest. In the breath-holding duration test, subjects were asked to take a deep-breath, hold their breath for as long as they could, and then exhale. The duration of breath-holding was recorded in seconds, with longer duration indicating better lung capacity. Lung capacity results were further validated using a TruZoneTM Peak Flow Meter, which recorded results in liters. In this test the participants were asked to take a deep-breath and blow air through their mouths into the meter as fast as they could (MacDonald, Dixon, Cohen, & Hazlitt, 2004). Two training and practice trails were conducted before the actual data was collected. Subject blood pressure, including systolic and diastolic, was measured after participants had rested for at least 10 minutes, using a digital sphygmomanometer (OMRON - HEM707) and recorded in mmHg.
Hand-grip strength in the dominant hand was measured using a digital handgrip dynamometer (TKK - 5101), with results (in kilograms) calculated by the average of three measurements (Brooks, Woodruff, Wright, & Donatelli, 2005). To ensure uniformity, hand-grip strength was measured in the second handle position for all participants. The dynamometer was not adjusted for hand size and grip span because standardization was necessary to increase reliability, and it has been shown that middle grip spans provide greater force than the smallest or largest grip spans (Blackwell, Kornatz, & Heath, 1999).
The sit-and-reach test was used to measure subject lower body flexibility. The test was administered using a specially constructed box that had a slide ruler attached to the top (Lemmink, Kemper, DeGreef, Rispens, & Stevens, 2003). The box, 33 centimeters in height, was placed against a wall, with enough room left for a subject to sit opposite the box with legs straight in front of her and bare feet against the box. Keeping her knees locked, the participant reached for the slide, smoothly pushed it as far away as possible, and then held the position for two seconds. The extent that the participants could reach forward while sitting on the floor was recorded in centimeters. After one practice trial, the best score of three formal trials was recorded. Higher scores indicated better performance (Lemmink et al., 2003).
The chair-stand test was used to evaluate lower limb muscle endurance. Subjects were asked to stand up and sit down with their arms folded across their chest, using an armless chair. The number of chair stands completed within 30 seconds was recorded (Rikli & Jones, 2001). A one-leg-stand test was used to measure balance, with subjects asked to stand behind a chair on a flat surface without shoes or socks, put their hands down by their sides and lift one leg two to five centimeters above the ground with their eyes open (Manini, Cook, VanArnam, Marko, & Ploutz-Snyder, 2006). The duration of the one-leg-stand was recorded in seconds.
Range of motion included shoulder flexion, shoulder abduction, hip flexion, and hip abduction on both right and left sides. A goniometer was used to measure degrees of flexion and abduction. Subjects were asked to stand up while shoulder range of motion was measured, and lie down on a mat while hip range of motion was measured.
All measurement devices were frequently used in the clinical settings with high expert content validity. Three sequential trial tests were employed for each measurement device, with intra-class correlations all exceeding .80. The devices used for physical measures were maintained by the project manager, who calibrated them before each data collection in order to minimize error and maintain study integrity.
Various questionnaires were used to measure subject sleep quality, depression state, and the self-actualizations of physical and psychological health. The sleep quality of subjects was measured with the Pittsburgh Sleep Quality Index (PSQI), an 18-item, self-reported questionnaire that assesses quality of sleep and sleep disturbances over a one-month period (Buysse, Reynolds, Monk, & Berman, 1989). A PSQI score was determined as the sum of the scores of the seven subscales and ranged from zero to 21; the seven subscales included: subjective sleep quality (1 item), sleep latency (2 items), sleep duration (1 item), habitual sleep efficiency (2 items), sleep disturbances (9 items), use of sleeping medications (1 item), and daytime dysfunction (2 items). A high score indicates more severe complaints and worse sleep quality; a score of five and above on the PSQI total scale is associated with clinically significant sleep disruptions, including insomnia and major mood disorders (Buysse et al., 1989). The Chinese version of the PSQI is available and has been widely used. In a sample of 96 Taiwanese older adults, the Cronbach's alpha for the PSQI was calculated as .84 (Tzou, 1993).
Depression in subjects was measured using the Taiwanese Depression Questionnaire (TDQ). The TDQ is an 18-item, Likert-type depression screening scale designed to measure a person's feelings about his/her physical and emotional states during the past week. Subjects were asked to reflect on the frequency of 18 physical or emotional expressions during the past week: 0 = never or less than one day a week; 1 = sometimes or one to two days a week; 2 = usually or three to four days a week; 3 = always or five to seven days a week. Possible scores range from zero to 54; a score of 19 or above indicates the possibility of depression and warrants further evaluation by a psychiatrist or counselor. In a sample of 107 community subjects, a Cronbach's alpha coefficient of .90, a sensitivity of .89, and a specificity of .92 at the cut-off score of 19 were reported (Lee, Yang, Lai, Chiu, & Chau, 2000).
The SF-12 Health Survey Chinese version was used to measure subjects' physical and mental health self-actualization. The SF-12 Health Survey is a short version of the SF-36 Health Survey, which is a self-reported, Likert-type scale designed to assess respondents' health status (Ware, Snow, Kosinski, & Gandek, 1993). It has two components that measures eight health concepts. The physical health component included concepts of physical functioning (2 items), role-physical (2 items), bodily pain (1 item), and general health perceptions (1 item). The mental health component included concepts of vitality (1 item), social functioning (1 item), role-emotional (2 items), and mental health (2 items). A high score indicates better physical and mental health (Ware, Snow, et al., 1993). The SF-12 is highly correlated with SF-36 in that Pearson correlation coefficients of .95 for the physical health component and .97 for the mental health component were reported (Ware, Kosinski, & Kerller, 1998). The SF-12 has been used widely with various populations. Cronbach's alpha coefficients have all been reported above .70 (Ware, Kosinski, et al., 1998).
This study was approved by the Institutional Review Board of the university. Following approval by the administrator of the local senior activity center, potential subjects were contacted by center staff, who submitted the names of those willing to participate in the study to the research team. The researcher met with each potential participant individually, explained the purpose of the study and the use to be made of the data, and requested those still willing to participate to sign a written informed consent form. It was emphasized that participation in this study was voluntary and that participants were free to withdraw from the study at anytime. The information revealed by the participants was kept confidential and only group data were presented without revealing the identity of the participants.
Statistical Package for the Social Sciences (SPSS) Version 10.1 was used to analyze data. Descriptive statistics such as mean, standard deviation, range, and frequency distribution were used to describe the profiles of the subjects from demographic data gathered. A paired t test was used to test mean differences between pre- and post-test measurements.
Demographic Profiles of the Participants
All participants were female and ranged from 60 to 86 (68.93 ± 9.14) years of age. Many were widowed (57.10%), lived with their family (57.10%), and had completed only a six-year elementary education (42.90%). Participants lived healthy lifestyles with no smoking or drinking habits (100%). Most (71.40%) were regular exercisers, with an average of 3.71 ± 3.07 exercise activity sessions per week. The cognitive function of the participants was intact, with an average SPMSQ score of 9.79 ± 0.58. Most participants (57.10%) had no chronic illnesses, with the average number of chronic illnesses reported by the participants 0.50 ± 0.65. The most frequent chronic illness reported by participants was hypertension (21.40%). An average score of 100 in the Barthel Index further indicated that participants were independent in self-care (i.e., in activities such as bathing, eating, or toileting).
The average body fat percentage of the subjects significantly decreased from 28.29 ± 6.80% at baseline to 26.07 ± 6.92% upon completion of the four-week silver yoga intervention [t(13) = −4.49, p = .001]. Although average body height of the subjects increased slightly, and the mean body weight and BMI of the subjects decreased slightly, these mean differences between pre- and post-test scores were not statistically significant (0.39 ± 0.82 cm, p = .095; −0.24 ± 0.77 kg, p = .257; −0.22 ± 0.44, p = .081; respectively) (see Table 1).
The average systolic blood pressure of subjects decreased significantly from 142.14 ± 22.34 mmHg at baseline to 122.93 ± 12.85 mmHg at the end of the four-week silver yoga intervention [t(13) = −3.97, p = .002]. Mean diastolic blood pressure also decreased by an almost significant level (the mean difference between pre- and post-test scores was 4.21 ± 7.88 mmHg [p = .067]). However, mean differences between pre- and post-test scores on breathholding duration and lung capacity were not statistically significant, 4.57 ± 8.86 seconds (p = .076) and 18.21 ± 62.62 liters (p = .296), respectively (see Table 1).
Hand-grip strength, lower body flexibility, lower limb muscle endurance, and balance
The average one-leg-stand duration of subjects increased significantly from 11.36 ± 11.74 seconds at baseline to 21.07 ± 21.19 seconds at the completion of the four-week intervention, [t(13) = 2.80, p = .015], indicating that subject balance had significantly improved. Hand-grip strength, lower body flexibility, and lower limb muscle endurance of the subjects improved, but not significantly. Mean differences between pre- and post-test scores for these items were 0.40 ± 1.97 kg (p = .461), 2.04 ± 5.43 cm (p = .184), and 1.79 ± 5.82 times/minute (p = .272), respectively (see Table 2).
Range of motion
The shoulder flexion and shoulder abduction of the subjects on both right and left sides improved significantly at the end of the four-week silver yoga intervention. Mean differences between pre- and post-test scores were 9.43 ± 11.60 degrees for the right shoulder flexion (p = .009), 12.79 ± 17.69 degrees for the left shoulder flexion (p = .018), 9.64 ± 12.49 degrees for the right shoulder abduction (p = .013), and 11.79 ± 13.37 degrees for the left shoulder abduction (p = .006) (see Table 2). The right hip flexion of subjects also improved significantly, from 107.57 ± 13.91 degrees at baseline to 124.79 ± 27.39 degrees at the end of four-week silver yoga intervention, [t(13) = 2.21, p = .046]. The mean difference between pre- and post-test scores on the left hip flexion was nearly significant, 14.64 ± 25.64 degrees (p = .052). However, mean differences for the right hip abduction (1.86 ± 14.00 degrees, p = .628) and left hip abduction (0.57 ± 15.09 degrees, p = .889) were not statistically significant, although they improved slightly (see Table 2).
Physical health actualization
Participants had mean self-actualized physical health scores of 44.46 ± 9.46 at pre-test and 50.22 ± 5.13 at post-test. The mean difference of 5.76 ± 10.41 was nearly significant, [t(13) = 2.07, p = .059] (see Table 3).
The average PSQI scores for subjects were 3.71 ± 1.90 at pre-test and 4.00 ± 2.39 at post-test, which were both under the cut-off point of five, indicating no clinically significant sleep disruptions. The difference between these two values was not statistically significant, [t(13) = 0.54, p = .598]. For the seven subscales of the PSQI as a group, average sleep disturbances decreased significantly from 1.14 ± 0.36 at baseline to 0.79 ± 0.43 at completion of the four-week silver yoga intervention, [t(13) = −2.69, p = .019] (see Table 3).
Average TDQ scores for subjects decreased, but not significantly, from 4.86 ± 6.07 at baseline to 2.00 ± 1.88 at the end of the four-week silver yoga intervention, [t(13) = −1.83, p = .090] (see Table 3).
Mental health actualization
Means of the self-actualized mental health scores of participants were 54.92 ± 7.11 at pre-test and 54.33 ± 8.04 at post-test. However, the mean difference of 0.60 ± 11.47 was not statistically significant, [t(13) = −0.19, p = .849] (see Table 3).
After the four-week silver yoga intervention program, participant body fat percentage and systolic blood pressure were significantly decreased; results that are congruent with Damodaran et al. (2002). Sleep disturbances were minimized and support the findings of Cohen et al. (2004). Subjects' balance and range of motion on their right hip flexion and shoulder flexion and abduction on both right and left sides improved significantly. This improvement, not often touched upon in earlier research literature, represents one of the crucial findings of this study. In the silver yoga program, various postures were designed to be performed in different poses, such as standing, kneeling, sitting, supine, and prone. These postures were based on six primary types of movements: flexion, extension, hyperextension, abduction, adduction, and rotation. They focused on increasing older adults' range of motion and progressive muscle relaxation, with special consideration given to physical abilities and tolerances (Chen, Tseng, et al., 2007). Through static physical postures, yoga uses stretching to improve muscular strength and flexibility, and the progression through a sequence of postures is intended to challenge blood vessels, muscle strength, joint flexibility, and balance (Luskin et al., 2000). Thus, the systolic blood pressure of participants decreased significantly and the balance and participant range of motion improved significantly through these postures. In addition, during the progress of static posture changes, body fat was consumed even though the silver yoga program represents a low to moderate intensity exercise. Thus, a significant decrease in body fat percentage was found in this group of participants.
Although a trend of improvement was observed in the remaining physical and psychological health indicators, these findings were either nearly significant or not significant statistically. These nearly or not significant results may be due to reasons that include: (1) the limited convenience sample size of the 14 female subjects who completed the study may have decreased the probability of detecting a significant difference that might typically exist and (2) the short duration of the four-week intervention period may not have been long enough to have a significant effect on the health status of some individuals. Subjective evaluations made by participants supported these two lines of thought. Participants expressed the opinion that they enjoyed the program very much, which was evidenced by the low withdrawal rate and high attendance.
While this was the first attempt to establish preliminary evidence for the efficacy and utility of the silver yoga program in older adults, the research design was exploratory. There were study limitations related to the sample selection process and research design. In this study, a convenience sampling strategy, rather than probability sampling, was used. Although both inclusion and exclusion criteria were clearly stated and helped guide the investigator in selecting subjects, it is possible that some older adults who met the sample selection criteria but who represented critical differences from the sample studied were not recruited, such as male seniors or those with mild dependency levels in their daily activities. Further, a one-group, pre-post test was used in this study. Without a comparison or a control group, many confounding factors and possible explanations could influence the interpretation of the results. For example, both the participants and the investigator were not in a double-blind situation concerning the study intervention. The investigator might have been more aggressive in measuring post-intervention data and participants may have been keen to show they had improved as a result of program participation. A randomized control trial with a large random sample could provide stronger causal relationships for intervention study results. Finally, the maturation effect due to repeated measurements may have impacted upon study results. One must be cautious in interpreting and generalizing the findings of this study to other populations.
This exploratory study revealed fairly positive health promotion outcomes of applying the silver yoga exercise program with a sample of healthy community-dwelling female seniors. Although nearly significant results were found in many health indicators in this study, they only suggested the directions that the practice of silver yoga might take in a larger study. As a trend of desired positive health changes in this small sample of female seniors was observed in the study, it is recommended that the silver yoga program be applied to a larger senior population for a longer intervention period to examine further its effects. Further, since no negative effects or complaints regarding the silver yoga program were reported by participants, it is recommended that the silver yoga program be incorporated as an activity program in senior activity centers or community-settings to promote the health of community-dwelling older adults.
Sincere appreciation is directed by our research group to the National Science Council, Taiwan for funding this study (NSC 94-2314-B-242-006), to Professor Frank Belcastro for his superlative manuscript editing, and to 16 wonderful older adults and the staff of Kaohsiung County Senior Activity Center for their generous participation.
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