BACKGROUND AND PURPOSE
Substantial evidence demonstrates that exercise has health and performance benefits for older adults in general1,2 and specifically for persons with Parkinson disease (PD).3-5 Emerging data from animal studies raise the possibility that exercise might also have neuroprotective benefits.6,7 For those with PD, exercise intervention studies demonstrate improvement in a variety of outcome measures, including overall measures of physical function,3,4,8,9 quality of life,3, 9-12 balance,3,10, 13-16 gait,17-21 strength,3,14,15,22,23 economy of movement,24 and spinal flexibility.13 However, after termination of supervised exercise, these measures may return toward baseline.8 Given that PD is a progressive condition, continued regular physical activity is likely required to sustain these benefits. These individuals need to establish consistent exercise habits that can persist without the need for ongoing external supervision.
This study was designed to identify factors that might assist health care providers in promoting continued exercise habits for people with PD. To this end, we conducted a qualitative interview-based investigation to learn about the motivators and barriers to ongoing physical exercise in persons who had graduated from, or dropped out of, an exercise study referred to as the Stay Active With Parkinson Disease (Stay Active) study. Stay Active was a 16-month, prospective, randomized, controlled study that compared outcomes associated with participation in 1 of 2 experimental exercise interventions with those of a control group participating in usual care exercises (NIH 1 R01 HD043770). Strategies that would assist participants in establishing consistent exercise habits were incorporated. These included discussions related to benefits and barriers to exercise, goal setting, and regular documentation of exercise behaviors.25 Participants in the 2 experimental exercise groups, both the aerobic exercise (AE) group and the flexibility, balance, and function (FBF) group, engaged in supervised exercise 3 times per week for 4 months. At the end of the 4 months, supervised exercise was tapered (ie, twice a week for 2 weeks and then once a week for 2 weeks). Subsequently, the participants met once monthly for supervised exercise for the remaining 11 months of the trial (total 16 months). Participants in the control exercise (CON) group were oriented to the program developed by the National Parkinson Foundation26 and instructed to exercise at home 3 to 5 times per week. These individuals participated in a once monthly group exercise session for 16 months. Strategies were incorporated that would assist participants in establishing consistent exercise habits. These included discussions with a coach related to benefits and barriers to exercise, goal setting, and regular documentation of exercise behaviors.
This was a qualitative interview-based investigation designed to elicit retrospective information related to exercise behaviors and attitudes during and after participation in an exercise study and to learn more about the current exercise attitudes and behaviors of the graduates and those who had enrolled but not completed the study. The Colorado Multiple Institution Review Board (COMIRB) approved this research. All participants gave informed consent.
In order to decrease the potential detrimental effects of elapsed time upon the participants recall, we elected to interview only those individuals who completed or dropped out from the study within the 14 months that preceded the interviews. Thirty-seven individuals who had enrolled in the Stay Active study (both those who had graduated [graduates] and those who dropped out [dropouts]) were contacted via telephone and invited to participate. All 19 participants who had graduated from the Stay Active study within the preceding 14 months were contacted. They were asked whether their significant other would also be willing to participate. Four graduates were unavailable for medical or logistical reasons and 15 agreed to participate. Overall, there were more graduates available for participation than dropouts. Indeed, at the time of recruitment for the current study, only 18 (15%) participants had dropped out since the beginning of the Stay Active study and only 4 had dropped out during the 14 months prior to the interviews. In an attempt to have a more representative sample, efforts were made to reach all 18 of the dropouts, regardless of the time that had elapsed since exiting the parent study. However, only 3 of these dropouts agreed to participate, and only 1 of these 3 participants had left the Stay Active study within 14 months of the interviews. Ten dropouts declined participation, and we were unable to contact 5 individuals who had dropped out. Of the 3 individuals who had dropped out of the parent study and agreed to participate in the interview, the reasons given for leaving the parent study prematurely did not differ substantially from the larger group of 18 individuals who had dropped out.
The investigators designed the interview protocols using the following strategy: Major areas of inquiry were identified and used to create an initial set of questions. Scripts were developed by the research team through an iterative process. Pilot interviews were conducted with 4 participants who had graduated more than 14 months previously. Feedback from these individuals was used to further refine the script, eliminate redundancy, and clarify the intent of ambiguous questions. The final set of questions covered the following content areas: (1) reasons for participating, (2) experience during the study, (3) activity following the study, and (4) suggestions to facilitate activity and exercise.
Interviewers were graduate students in counseling psychology with extensive experience in conducting interviews. Each received 3 hours of education specifically related to PD, including discussion of some of the challenges faced by these individuals and their family members. Interviewers practiced with participants who had graduated more than 14 months previously. All interviews were conducted under the supervision of one of the investigators (C.M.) who had not been associated with the parent study.
After giving informed consent, each participant completed a 30- to 40-minute interview and each spouse completed a 15- to 20-minute interview. Interviews were recorded and the audiotapes were transcribed.
Responses were clustered according to content area. Trends were identified from frequency of occurrence. When appropriate, means (SD) were determined. Although an effort was made to obtain responses to all questions, sometimes questions were incompletely answered, unanswered, or inadequately answered in regard to the intent of the inquiry. Therefore, the total number of responses reported in this text differs depending upon the particular question that was posed.
Participants included 15 graduates and 3 dropouts of the Stay Active study and the spouses of each. Graduates included 11 men and 4 women (Table 1) with mean (SD) age of 68.1 (10.9) years. Dropouts included 1 man and 2 women with a mean age of 74.3 (4.9) years. Graduates were in stages 2 and 2.5 of HY with a mean UPDRS motor score of 23.1 (11.6); dropouts were in stages 2.5 and 3 of HY with a UPDRS motor score of 27.0 (7.4).
Five graduates from each of the 3 exercise groups (ie, AE, FBF, and CON) participated in the interviews. Of the dropouts, 2 were from the AE group and 1 from the FBF group. Interviews were conducted within 3.5 to 14 months (mean = 8.7 [2.8]) after graduation. All of the participants were married and living with a spouse. More than 75% of those who participated in the interviews indicated that they had exercised in the past (prior to the diagnosis of PD); more than 25% indicated that they had engaged in structured exercise at some point in time. The pattern of many responses was similar for both graduates and dropouts (see Table 2, Supplemental Digital Content 1, http://links.lww.com/JNPT/A9, which lists the most frequent responses). For this reason, the responses from graduates and dropouts are discussed together, except where explicitly stated.
Motivations for Entering the Stay Active Exercise Study
Graduates and dropouts identified a number of reasons for agreeing to participate in the study. Motivations were similar for both groups and included the following: The desire to delay the progression of PD (5 participants [28%]), the recommendation of a physician (5 participants [28%]), and the conviction that exercise would help to manage their parkinsonian symptoms (4 participants [22%]). Other motivators included the following: to further research, to get support from family members, curiosity about the possible benefits of exercise for PD, to create momentum for engaging in regular exercise, management of depression, and to be able to continue to engage in activities that they valued in their daily lives.
Experience During the Study
All participants reported that the study was helpful for increasing their activity levels. On a scale of 1 to 5 (1 = “not at all helpful” to 5 = “extremely helpful”), average scores from the FBF and AE groups indicated that the programs were helpful (means [SD] = 4.0 [1.16] and 4.4 [0.55], respectively). Individuals in the CON group gave a lower estimate: mean (SD) = 3.2 (1.48). Two of the 5 participants (40%) in the CON group indicated that the exercises were not sufficiently challenging or were boring. This comment was not heard from members of the other groups.
The 15 graduates were asked about their motivations for remaining in the study. Six of the graduates (40%) identified commitment to the project; 3 (20%) enjoyed the structure of the program for supporting regular exercise; 3 (20%) cited awareness of feeling “better” because of the exercise; and others mentioned interest in the study outcome (1 [7%]), family support (1 [7%]), and a desire to slow the progression of PD (1,7%) as motivators for completing the study. Graduates were also asked about factors that made participation in the study difficult. They reported problems with transportation to the study site (5 [33%]), other time conflicts (5 [33%]), and non–PD-related medical conditions (5 [33%]).
All participants were asked about the importance of setting goals. Eleven of the graduates and 1 dropout (12 participants [67%]) indicated that goal setting was helpful in keeping them focused upon exercising (both during the study and after), while the remainder of the participants (6 [33%]) felt that goal setting was not useful for them. Although the interviews were not specifically constructed to elicit personal preferences for exercise, it was evident in reviewing the transcripts that the group dynamic was an important positive motivator for some participants, whereas other individuals found it more desirable (ie, practical or consistent with their preferences) to exercise on their own.
Activity Levels After the Study
The majority of participants continued to engage in regular exercise or activities to some degree after graduation. Types of exercise included skiing, sailboat racing, treadmill training, swimming, weight lifting, walking, exercise with elastic bands, stretching, strengthening exercises, stick exercises, bike riding, golf, bowling, Wii Fit (Nintendo) games, lawn work, and gardening.
Although participants exercised to some degree after the study, there was a general decline in activity levels. Not all participants were able to estimate their ongoing physical activity. On average, of the 9 who were able to estimate their activity, members of the AE and FBF groups estimated ongoing physical activity at 83.5% to 91.7% of their study maximum, respectively. In contrast, 5 members of the CON group estimated their current activity at 30% to 80% (average 63.5%) of the maximal activity levels reached during the study. In all 3 groups, participants who had completed the study a longer time before the interviews reported lower current activity levels.
Reasons given by the graduates for a decrease in activity were varied. Four of the 15 graduates (27%) reported non–PD-related declines in health after the study and indicated that they were not able to do as much. One (7%) AE group participant cited as a barrier a progression of lower extremity rigidity related to PD. Time constraints and external demands were important factors limiting exercise participation for 3 of the graduates (20%). Two individuals (13%) from the CON group stated that they were unmotivated to exercise.
When graduates and dropouts were asked about their motivations to continue exercise after the study, they cited hope of preventing worsening of PD symptoms (4 [22%]), family support (3 [17%]), feeling physically better with exercise (3 [17%]), knowledge that exercise is good for you (3 [17%]), and feeling emotionally better with exercise (3 [17%]). After the study, most (11 [61%]) participants were not exercising with their spouses, 5 (28%) reported that they were exercising with their spouses (including 1 dropout), and 2 (11%) did not respond to the question.
Suggestions to Encourage Exercise and Activity
The last series of questions were intended to elicit feedback as to what might be done in the future to encourage study participants to greater activity and exercise. Two of the 5 parti-cipants (40%) in the home exercise group expressed a wish for periodic adjustments to the prescribed program to increase the level of challenge and to improve their motivation to maintain regular exercise. Three (20%) of the graduates (1 from each group) suggested combining activities in a future study (eg, adding aerobics and yoga to the FBF program). Other suggestions included a videotape of the home exercises performed by the CON group, meeting more than once monthly in the home exercise maintenance phase, more individualization of the FBF program, flexible scheduling, compensation for mileage, and additional one-on-one instruction about how to do home exercises.
Six of 18 participants (33%) wanted scientific evidence supporting their assumptions that exercise is beneficial in PD (eg, for symptom management and/or neuroprotection). Four (22%) felt that health care providers should be aware of appropriate exercise opportunities that are available in their communities and 4 (22%) suggested that their providers should be informed about available research studies in which they might participate. Four participants (22%) wished that their health care providers would discuss exercise with them during their medical appointments and encourage them to be active. In addition, participants indicated that they wanted appropriate exercise facilities and programs that are close to their homes, tailored to their individual interests, enjoyable, affordable, and easily accessible (including ease of parking).
Spousal Impressions of the Benefits of the Exercise Study
The majority of spouses (12 [67%]) (including spouses of 2 of the dropouts) reported that the study had been helpful in some way to their partners, whereas 2 (11%) said that it was not helpful and 3 (17%) were unsure. Spouses offered a variety of reasons for why they thought that participation in the study had been beneficial. Some commented that involvement in the study had helped their partner to get out of the house (3 [17%]) and to focus on a goal (2 [11%]). Responses from the spouses of graduates and dropouts did not differ from each other in any discernable pattern.
When asked about the factors that motivated their partners to complete the study, the spouses of the graduates gave a variety of responses. Tenacity for following through on one's commitments emerged as the most commonly cited motivating factor (4 [27%]). Other motivational factors mentioned by the graduates’ spouses included management of PD symptoms, hope that the exercise would slow or stop PD progression, encouragement from family members, seeing other people with PD who seemed to be doing better because they exercised, and a belief that exercising would help the person to be able to continue participating in other meaningful activities. Six of the 18 spouses (33%) (5 of graduates and 1 of a dropout) reported that they exercised with their partners during the time period when their partner was actively involved in the exercise study. After participation in the study ended, 3 (20%) of the graduates’ spouses and 2 (67%) of the dropouts’ spouses reported that they exercised with their partners.
We were particularly interested to know more about what caused individuals to drop out of the study. All 3 of the dropouts reported that they had been very committed to the program and had wanted to continue. Two (67%) individuals (both from the AE group) dropped out secondary to physical problems unrelated to the study. One (33%) participant (from the FBF group) reported problems with the travel distance to the exercise venue and competing time commitments.
Two of the 3 study dropouts (67%) reported that they were continuing to exercise, but at a lower level (50%-60% of the study intensity). Of the 2 dropouts who continued to exercise, 1 was motivated by the knowledge that exercise is generally healthful and the other by the hope that exercise would thwart the progression of PD symptoms. Only 1 individual indicated a lack of any significant physical activity; that individual was a dropout from the AE group. She cited knee pain, lack of energy, and the need to take care of an aging parent as reasons for not pursuing physical exercise.
To have a broader view of the characteristics of the dropouts, and because there were so few dropouts available, we also examined the data from all 18 of the individuals who dropped out of the parent study. Reasons given for leaving the study included medical issues that were unrelated to the study (7 [39%]), inability to commit to the program (2 [11%]), dissatisfaction with the program (2 [11%]), and travel distance from site (1 [5%]). The remaining 6 participants (33%) withdrew for unknown reasons. Both individuals who dropped out secondary to dissatisfaction with the program were in the CON group.
Over the past decade, great strides have been made toward understanding the positive effects of exercise for persons with PD.3,5,9,16,23 Much less is known about the barriers and motivators experienced by individuals with PD, which influence long-term adherence to exercise programs. To learn more about participants’ attitudes towards exercise as well as their experiences during a structured exercise trial, we conducted this qualitative study. The purpose of qualitative studies is to learn about a topic in more depth than is possible in a quantitative study. Results of a qualitative study can be used to identify issues that could be explored in future experimental studies or could provide insight for practitioners as they make individualized decisions when working with persons who have PD. Due to the progressive nature of PD, it is essential that people with this disease develop and adopt ongoing exercise and activity habits to sustain benefits accrued during supervised interventions. The current investigation provides initial insights into this critical issue.
For the group of individuals who participated in this study, the most frequently cited reasons for enrolling in the parent exercise study included the anticipation that the exercise might help to control PD-related symptoms, as well as affording health and psychological benefits of exercise. Yet to be determined, and of critical importance, is the extent to which individuals without a prior appreciation for exercise can be motivated to exercise. Because PD is a chronic and progressive disorder, it is essential that people with this disease develop and adopt exercise and activity habits to sustain benefits accrued during supervised interventions. Given the limited resources of the health care system, it may be appropriate to reserve these resources for those who are likely to continue with long-term exercise. For this reason, studies that identify characteristics of individuals who are most likely to adopt long-term exercise habits are needed.
Overall, feedback from participants highlights the observation that there is no “one-size-fits-all” approach to exercise for these individuals. Indeed, individualization of an exercise program has been shown to increase adherence to exercise.27 Based on the themes that emerged from these interviews, several factors may help guide the individualized exercise prescription. Clinicians may be in a better position to promote ongoing exercise adherence if they first identify whether the individual prefers group versus solo activities. Some of the participants indicated that periodic adjustment of the exercises might help an individual maintain interest and feel challenged by the activities. Thus, health care providers may consider revising exercise recommendations on a regular basis. In addition, there was an appeal for a combination of different types of exercise, rather than a single form (eg, flexibility plus aerobic activity). This request is in line with best practice recommendations for older adults, which have called for programs that incorporate flexibility, strengthening, and aerobic exercise.27,28 For people who have enjoyed regular exercise in the past, it may be helpful to draw on those experiences to encourage them to resume exercise. For those who have lacked prior exercise habits, or who find exercise aversive, it could be helpful to identify rewarding activities. In this regard, it is important to note that the form of “exercise” identified by participants was wide ranging and included formal exercise and increased activity generally. Yet to be established is the benefit of increased activity as compared with formal exercise programs.
On the basis of interviews with the spouses, it appears that some of the spouses helped to motivate their mates to get to their scheduled sessions. For supportive spouses such as these, it may be feasible and useful to bring them more actively into the exercise programs (eg, exercising together or in parallel). However, in other instances, the spouse and partner demonstrated a nonsupportive marital relationship, in which case the spouse may have played a neutral or negative role.
A striking finding from these interviews relates to exercise habits following graduation from the Stay Active study. During the course of the exercise study, participants showed a high level of adherence to their assigned exercise programs and were positive about the benefits. Yet, after graduation, most participants reported a decrement in activity. This occurred in spite specific strategies in the Stay Active study to assist them to develop exercise habits and in spite of their reported continued motivation for exercise. This finding highlights the importance of ongoing support to continue to exercise in the face of the barriers that arise in daily life.
Maintaining activity following a supervised exercise intervention is at least as important as the supervised exercise intervention itself. Participants clearly identified a desire for more accessible community resources to continue to exercise (eg, well-organized community-based exercise programs that might support ongoing exercise habits). These findings echo those of other groups trying to promote exercise in the general older adult population.1, 28-30 Comments from participants emphasized the importance of clinicians assisting them in the transition from a structured exercise intervention or formal therapy into informal modes of exercise. Participants clearly indicated that they would like this support from physicians and other health care providers. Therapists might also provide benefit to the individuals with PD with whom they work by educating physician colleagues about available community resources.
Although transition to the community resources may be key to maintaining greater activity, it is also critical for physical therapists to recognize the importance of long-term follow-up with individuals who have PD. It is necessary to adjust the exercise and activity recommendations as the disease progresses. Thus, physical therapists may need to reevaluate individuals with PD, just as the neurologist routinely assesses the need for adjustment of medications. Furthermore, because the barriers to exercise may change as the disease evolves, ongoing discussions are important to identify the impediments and assist the individual in identifying solutions.
Finally, it was evident that there were a wide variety of responses and attitudes; typically fewer than 40% of participants identified the same problems or solutions. These individual differences demonstrate how important it is for clinicians to explore the specific key concerns of their patients to design strategies to assist in long-term adherence to exercise and activity.
The limitations of this study should be acknowledged. The initial intent of this study was to find out what motivated the graduates of the Stay Active exercise study to engage in the research, complete the protocol, and then continue to exercise after the formal phase of the research study was completed. We also wanted to better understand why individuals dropped out of the study. Because of the low number of study dropouts within the 14 months prior to the start of the interviews, we expanded our recruitment window to try to include even those who had left the study more than 14 months before the interviews commenced. However, we were still unable to recruit more than 3 of these individuals. By the very nature of dropping out of a study, it is probable that these individual may not want to participate in follow-up, further limiting the potential dropout sample. Thus, there was a large sample discrepancy between the number of graduates (15) and dropouts (3) who were interviewed for this study. However, a direct comparison between the graduates and the dropouts was not part of the original intention of this qualitative study.
Participants were graduates of an exercise intervention in which they voluntarily enrolled and may not be representative of the general population of persons with PD for whom interest in exercise varies considerably.31 Regional differences in exercise readiness and adherence may also have influenced the results as the Stay Active study drew participants from a relatively active community. Findings might be different if the sample had been drawn from another area of the country or a community that had less interest in exercise. Another potential issue is the variability in the time span from when the participants graduated from or dropped out of the parent study relative to when they underwent the interview. This timing difference may have affected the accuracy of the recall. Finally, the form of exercise was randomly assigned, and we cannot determine how the participants might have reported about their experience had they exercised in programs tailored for their specific needs.
In this investigation, we did not quantify the amount of formal exercise that each individual undertook after the study, nor did we distinguish the amount of structured exercise versus general physical activity in which the participants engaged on the basis of the interviews. Future investigations should examine these questions more specifically. Also, this qualitative investigation was not designed to reveal the physical, psychological, or demographic characteristics of those individuals with the highest degree of adherence to exercise after the study. However, these issues should be explored in future investigations of an experimental (versus qualitative) nature.
Much has been learned about effective forms of exercise for persons with PD.3,5,22,25 However, findings from this qualitative examination of attitudes and experiences of individuals who had been participants in an exercise study indicate that it is equally important to determine how to motivate and enable people with PD to engage in these activities and to develop enduring exercise habits. Otherwise, gains made during short-term exercise efforts may be lost. Information from this qualitative research study may be useful to clinicians who are trying to optimize adherence to exercise and to researchers who are attempting to limit dropouts from exercise-oriented clinical trials.
This work could not have been completed without support by a grant from the Davis Phinney Foundation. We are grateful to all the participants who graciously gave of their time and insight. We greatly appreciate Pamela Mettler and Jan Euley, PT, for their assistance with data collection and management, and students in the Counseling Psychology program at the University of Denver for their assistance interviewing the participants. We give special thanks to Miriam Morey, PhD and Julie Keysor, PT, PhD for their invaluable assistance in the design of this study. The parent study was funded by NIH # 5 R01 HD043770-05 and NIH MO1 RR00051.
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