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Multiple Sclerosis 2007; 13: 652659
Enhancing physical activity adherence and well-being in multiple sclerosis: a randomised controlled trial E McAuley1, RW Motl1, KS Morris1, L Hu1, SE Doerksen1, S Elavsky2 and JF Konopack1 Individuals with multiple sclerosis (MS) are more sedentary than the general population, increasing their propensity for reduced functional ability, mobility, and activities of daily living. Self-efficacy has been one of the most consistent determinants of physical activity across populations, including those with MS. However, no studies exist that have attempted to influence self-efficacy in MS patients, in an effort to improve physical activity participation. We conducted a three-month randomised, controlled trial (n /26), contrasting the effects of an efficacy-enhancement exercise condition and a control exercise condition on exercise adherence, well-being, and affective responses to exercise. Analyses indicated that individuals in the efficacy enhancement condition attended more exercise sessions, reported greater levels of well-being and exertion, and felt better following exercise than individuals in the standard care condition. Regardless of treatment condition, individuals with a stronger sense of exercise self-efficacy, who reported more enjoyment following the exercise sessions, demonstrated significantly greater adherence with the exercise program. We believe this to be the first empirical attempt to change physical activity behavior in persons with MS using a well-established theoretical framework to drive the intervention. Continued examination of self-efficacy as a determinant of behavior change in individuals with MS is needed. Multiple Sclerosis 2007; 13: 652 659. http://msj.sagepub.com Key words: adherence; multiple sclerosis; physical activity; self-efficacy; well-being
Physical activity has been suggested as a behavioral modality for improving MS [1], and managing the physical demands of MS [2], and there is experimental evidence to further indicate that exercise training is beneficial for the management of MSrelated symptoms [3,4]. Unfortunately, cumulative evidence from a recent meta-analysis indicates that individuals with MS engage in less physical activity than non-diseased populations [5]. Indeed, the difference between MS and non-diseased populations is considerable, approaching 1 SD. Given the high prevalence rates of physical inactivity among adults in the US [5], this finding is particularly alarming, as physical inactivity is associated with a host of disease conditions. One of the most widely adopted theoretical frameworks for understanding physical activity and other health behaviors is social cognitive theory [6]. The central agent in this framework is self-efficacy, or beliefs in one’s capability to success-
fully carry out a particular course of action. Selfefficacy has been consistently implicated as a determinant of adoption and maintenance of physical activity [7]. Although research examining correlates of physical activity among those with MS is limited, self-efficacy, enjoyment, and impairment have been associated with physical activity participation in individuals with MS [8,9]. Such evidence suggests that interventions designed to influence physical activity in those with MS should focus on enhancing self-efficacy [5]. This recommendation is consistent with other intervention approaches that have focused on increasing physical activity adherence [10]. In the event that such an approach can be successfully applied with MS patients, the public health yield of enhancing physical activity participation in this group could be considerable. As well as influencing exercise behavior, selfefficacy may also have implications for a variety of
1
University of Illinois at Urbana-Champaign, Urbana, IL, USA The Pennsylvania State University, University Park, PA, USA Author for correspondence: Edward McAuley, PhD, Department of Kinesiology and Community Health, University of Illinois, 336 Freer Hall, Urbana, IL 61801, USA. E-mail:
[email protected] Received 13 June 2006; accepted 5 September 2006 2
– 2007 SAGE Publications
10.1177/1352458506072188
Enhancing physical activity adherence and well-being in multiple sclerosis other favorable outcomes associated with physical activity participation in those with MS. For example, self-efficacy influences the types of behaviors that individuals choose to engage in, the degree of effort that they put forth in challenging tasks, persistence in the face of aversive stimuli, and the emotional consequences associated with behavior [11]. In the context of physical activity, self-efficacy has been associated with improved well-being responses resulting from physical activity [12], and perceptions of effort during physical activity [13,14]. Determining whether improvements in these states result from regular physical activity, and whether self-efficacy for exercise is associated with such positive outcomes in this population, is warranted. This study had two primary objectives. The first was to determine the effects of an efficacy enhancement intervention on adherence and perceptions of well-being following a three-month exercise program in a sample of individuals with MS. We were also interested in examining the effects of the intervention on affective and perceived exertion responses to acute exercise across the intervention.
Method Participants Individuals with MS were recruited from the local community to participate in this study. Recruitment efforts included contacting the local chapter of the National Multiple Sclerosis Society, media advertisements, and contacting individuals from previous studies of MS. After receiving initial contact from potential participants, individuals were screened by members of the research team to ensure eligibility. Eligibility criteria included: (1) having a definite diagnosis of MS; (2) being ambulatory with minimal assistance; (3) sedentary (defined as being physically active less than three times per week for 30 minutes each bout); and (4) willing to commit to the length of the program. Design The nature of the design was a randomized, controlled trial, consisting of an efficacy enhancement exercise condition, and a standard care exercise condition. Of the 53 participants initially showing interest, 27 did not to meet the inclusionexclusion criteria. The remaining 26 individuals were randomised into either the standard care (n / 13) or the efficacy enhancement (n / 13) exercise conditions. Six participants in the stanhttp://msj.sagepub.com
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dard care group and nine participants in the efficacy enhancement group completed all baseline and follow-up assessments. Participant flow is shown in Figure 1.
Measures Demographic and health status information Each participant was asked to provide current demographic information, including age, sex, race, education, annual income, and marital status (Table 1). In addition, basic health status information was obtained from each participant’s primary physician as part of a medical clearance for the study (Table 1). Self-efficacy The six-item Exercise Self-Efficacy (EXSE) scale was used to measure participants’ beliefs in their ability to continue exercising at a moderate intensity at least three times per week for 30/ minutes over incremental two-week periods [15]. Participants rated their confidence on a scale ranging from 0% (not at all confident) to 100% (highly confident). An efficacy score was calculated by summing all given response scores and dividing by the total number of items, resulting in a possible range of 0 100. Internal consistencies for the EXSE at both baseline and postprogram in the present study were excellent (a ’s /0.96). Well-being We used several measures to assess well-being. First, ‘global quality of life’ was assessed by the five-item Satisfaction with Life Scale (SWLS) [16]. Each scale item was rated on a seven-point scale, from strongly disagree (1) to strongly agree (7), with higher scores representing greater life satisfaction. Scores on the SWLS can range from 5 to 35. Pavot and Diener’s [17] review of research using the SWLS suggests that it is sensitive enough to detect changes in life satisfaction over the course of a clinical intervention. In the present study, internal consistencies of SWLS at baseline (a /0.96) and end of program (a /0.95) were excellent. Additionally, we used the 12-item Short Form Survey (SF-12) [18] to assess physical and mental health status. This measure is a shortened version of the Medical Outcomes Study SF-36 Short Form Survey, which was developed to assess health status in large-scale studies [19]. The SF-12 Multiple Sclerosis 2007; 13: 652 659
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E McAuley et al. Initial Contact Excluded: N=27 N=5: too active N=10: time commitment/schedule N=5: not ambulatory N=3: too old N=4: no further correspondence after initial contact
N=53
Randomized N=26
Efficacy Enhancement Condition
Standard Care Condition N=13
N=13
Attrition: N=2 – fatigue N=2 – schedule N=3 – symptom problems
Attrition: N=2 – illness N=2 – fatigue
Efficacy Enhancement Condition – Completed Trial N=9
Standard Care Condition – Completed Trial N=6
Figure 1 Participant flow through trial.
items provide summary measures of physical and mental health status, with scores ranging from 0 to 100, and standardised to have a population mean score of 50 and a standard deviation of 10.
Exercise adherence Exercise adherence was defined as the total number of class sessions attended during the three months (possible range 0 36). This was determined from daily attendance logs collected by the exercise leader at the end of each exercise session. Multiple Sclerosis 2007; 13: 652 659
Acute exercise responses Participants completed measures of enjoyment, affect, and ratings of perceived exertion following each exercise session. Enjoyment was measured by a Likert scale item in which participants indicated the extent to which they had enjoyed their exercise session that day. Scores ranged from 1 (‘not at all’) to 7 (‘very much’). Affective responses were assessed using the Feeling Scale [20], a single-item assessment of the basic good-bad core of affect that corresponded with how participants felt after exercising. This scale ranges from /5 (‘very good’) through 0 (‘neutral’) to /5 (‘very bad’). Finally, http://msj.sagepub.com
Enhancing physical activity adherence and well-being in multiple sclerosis Table 1 Sample demographics and health status
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Gender Male Female Marital status Married Single Divorced/separate Widow/widower
3 23
11.64 88.46
13 6 5 1
50.00 23.08 19.23 3.85
sion of general health-related topics. Workshops included mini-lectures on the following topics: (a) general benefits associated with increased physical activity (eg, building healthy bones, muscles, joints, improvements in self-image, and decreased risk of coronary artery disease); (b) exercise-related injuries and strategies for preventing and treating such injuries; (c) the contribution of proper nutrition to good health (eg, energy balance, proportion sizes, daily calorie intake, limiting the dietary fat intake, and the food guide pyramid); (d) health allergies and strategies for minimising the severity of attacks; and (e) importance of managing blood pressure and cholesterol.
Education B/College ]/College
14 12
53.85 46.15
Efficacy enhancement exercise condition
Variable
n /26 Mean
SD
Age Months after diagnosis
43.46 106.73
7.60 77.05
Frequency n
%
Annual income B/$20 000 B/$40 000 ]/$40 000 Ethnicity/race African American Caucasian
5 5 15
19.23 19.23 57.69
2 24
7.69 92.31
MS type Relapsing-remitting Secondary progressive Primary progressive
24 1 1
92.30 3.85 3.85
1 1 1 1
3.85 3.85 3.85 3.85
Disease status Pulmonary disease Hypertension Hyperlipidemia Diabetes
ratings of perceived exertion (RPE) were measured using Borg’s 15-point RPE scale [21]. Values on this RPE scale range from 6 to 20, with verbal anchors for odd numbers (eg, 7 /very, very light; 15 /hard; 19 /very, very hard). All measures were aggregated across the trial, and averaged to provide a single value of each measure across the intervention. Intervention Participants were randomised to either a standard care or efficacy enhancement exercise condition, delivered in bi-weekly workshops incorporated into a 12-week physical activity program. Staff contact hours were standardised between conditions. Standard care exercise condition The workshops designed for the standard care condition focused on the presentation and discusa
Workshops designed for the efficacy enhancement condition focused on the provision of efficacybased information relative to physical activity participation. Lectures plus discussion and minihomework assignments comprised the delivery mechanism for this condition. Topics covered in this intervention included: (a) the importance of realistic, challenging, and attainable goals; (b) common barriers to initiation and maintenance of exercise and strategies for overcoming these barriers; (c) monitoring of performance feedback; (d) strategies to promote realistic outcome expectations; and (e) importance of social support and networks within and outside the exercise environment. This was achieved through the formation of ‘buddy groups’, and viewing a DVD on social support, activity, and MS produced for this study. Recommendations and strategies to boost their confidence in their ability to remain physically active beyond program termination (eg, provision of contact information of fellow study participants, maintenance of ‘buddy groups’, physical activity programs in the local community)a was the focus of the final workshop. Exercise program Both groups participated in a three-month physical activity program, conducted in separate state-of-the art health and wellness centers under the supervision of trained exercise leaders, and met three times a week for 1 hour per session. Each exercise session began with a 10-minute warm-up, and finished with a 10-minute cool-down phase, both of which included instructor-led stretching exercises designed for MS patients. The remainder of the session consisted of aerobic exercise at an
Detailed information regarding intervention content is available from the corresponding author.
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intensity approximating 50% of their age-predicted maximum heart rate [22]. Participants were free to choose from a variety of cardiovascular machines, including treadmills, stationary cycles, and elliptical trainers. In addition to reducing the weightbearing component of activity, the latter two modalities also include a muscle toning component for the upper body. At the start of the program, the goal of all participants was to complete 10 minutes of exercise, and to increase this duration by 5 minutes each consecutive week. At the six-week mark, each participant was encouraged to complete 30 minutes of exercise at 50 60% of their predicted maximal heart rate. Weeks 7 through 12 focused on increasing the intensity of the exercise by increasing exercise heart rate to 60 75% of their predicted maximum heart rate. As individuals progressed at different rates, an emphasis was placed on continued activity rather than absolute time spent exercising at the prescribed intensity. Thus, during periods of relapsing disease symptoms, individuals were allowed to reduce their duration and/or intensity of exercise.
value carried forward. To examine the effects of the intervention on hypothesised study outcomes, we conducted either one-way analysis of variance or 2/ 2 (condition/ time) mixed model repeated measures multivariate analyses of variance. Relationships between baseline self-efficacy and overall adherence and acute exercise responses were tested with Pearson correlation coefficients. All analyses were conducted using the Statistical Package for the Social Sciences (SPSS V.14.0; Chicago, IL). Sample size and the intent-to-treat approach adopted made the finding of statistical significance difficult. As Rutledge and Loh [23] recently pointed out, even small effects can often have important clinical implications and are, thereby, important to report. Thus, we calculated the effect sizes (d) associated with the intervention using Cohen’s [24] approach of determining d as the Mtreatment / Mcontrol divided by the pooled standard deviation. As such, effect sizes can be considered as ‘small, d 5/ 0.2’, ‘medium, d :/0.5’, and ‘large, d ]/0.8’.
Results Procedures All procedures were approved by an Institutional Review Board and all participants completed a written informed consent. Following initial telephone contact and screening, participants were mailed a packet containing the informed consent, questionnaires, and information about the program (ie, location for testing, maps to the exercise location and our laboratory, and parking information). Upon completion of all baseline assessments, participants were randomly assigned to either the efficacy enhancement or standard care exercise group. Exercise logs were completed following each exercise session, checked for completeness, and collected by an exercise leader. The standard care and efficacy enhancement workshops were delivered on a bi-weekly basis after an exercise session, and were held in a meeting room adjacent to the exercise facility. Following the intervention, questionnaire packets were once again completed. At the end of the program, all participants were given a detailed listing of all exercise facilities in the local area.
Data analyses As attrition is always a major concern in exerciserelated interventions, we adopted a conservative approach to the treatment of the data. All analyses used standard intent-to-treat principles, with missing values on any variable replaced with the last Multiple Sclerosis 2007; 13: 652 659
Intervention effects on exercise adherence, perceived exertion and affective responses to exercise The overall multivariate effect for intervention condition on adherence was non-significant (F (2,23) /0.69, P /0.50). However, as can be seen in Table 2, the effects were in the predicted direction, with the efficacy enhancement condition attending more exercise session and exercising for more total minutes during the program. These medium effect sizes reflect the efficacy enhancement group exercising on approximately six more occasions (ie, two more weeks out of 12), and for a total of approximately 150 extra minutes across the three-month period. The overall multivariate effect for the intervention group on perceptual responses to exercise Table 2 Intervention effects on adherence and acute exercise responses
Outcome Exercise frequency Exercise duration Enjoyment RPE Affect
Condition Efficacy enhancement
Standard care
Effect size
24.23 (10.56)
18.61 (13.15)
0.47
576.81 (301.62)
425.56 (371.29)
0.45
4.25 (1.04) 13.43 (1.88) 2.52 (1.30)
4.40 (0.87) 12.15 (1.18) 1.82 (1.15)
0.15 0.63 0.57
Values represent mean (standard deviation); RPE, ratings of perceived exertion.
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Enhancing physical activity adherence and well-being in multiple sclerosis approached significance (F (3,22) /2.73, P /0.07). As can be seen from Table 2, the effects were once again in the predicted direction, with those participants in the efficacy enhancement condition reporting that they worked harder and that exercise made them feel better than the participants in the standard care condition. Both groups reported similar levels of enjoyment.
Intervention effects on well-being responses to exercise There was a significant time by intervention group multivariate interaction effect for well-being measures (ie, health status and satisfaction with life) (F (3,21) /3.43, P /0.04). Decomposition of this interaction revealed that participants in the efficacy enhancement condition maintained levels of satisfaction with life over the three-month period, whereas the standard care condition reported a decline in life satisfaction over time. Participants’ perceptions of physical health remained largely stable across time, while perceptions of mental health declined in both groups. Mean values across time are reported in Table 3.
Relationships between self-efficacy, affective responses, and adherence Correlations between baseline exercise self-efficacy, adherence (attendance) across the trial, and mean levels of enjoyment and feeling state responses during the program are shown in Table 4. As can be seen, regardless of treatment condition, individuals with a stronger sense of exercise self-efficacy, who reported more enjoyment following the exercise sessions, demonstrated significantly greater adherence with the exercise program (ie, attended more sessions). Feeling better during exercise, however, was not associated with adherence. Interestingly, more efficacious participants at baseline also Table 3 Intervention effects on well-being
Outcome
Condition Efficacy enhancement
Standard care
Physical health status pre Physical health status post Effect size Mental health status pre Mental health status post Effect size Satisfaction with life pre Satisfaction with life post Effect size
43.58 42.70 /0.07 44.34 41.58 /0.22 20.25 20.91 0.05
39.63 40.92 0.12 51.74 48.78 /0.32 24.92 21.07 /0.48
(12.24) (11.21) (12.02) (12.24) (11.73) (11.20)
Values represent mean (standard deviation).
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(10.61) (9.36) (6.31) (11.18) (8.00) (7.83)
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reported greater enjoyment, feeling better, and working harder during activity.
Discussion This small, randomised, controlled trial examined the effects of a self-efficacy enhancement intervention on adherence, well-being, and affective and exertion responses assessed following daily activity in a sample of individuals with MS. We believe this to be the first empirical attempt to change the physical activity behavior in persons with MS, using a well-established theoretical framework to drive the intervention. Although small in scope, the intervention outcomes are encouraging, and perhaps offer insight into potential methods for improving physical activity participation in this population. The moderate effect on adherence, as demonstrated by greater daily attendance to the exercise program, and more total minutes documented in exercise, is comparable to the intervention condition exercising for six more days and 150 more minutes over the three-month program than the control condition in the current study. We believe that these moderate effects are sufficient to warrant further examination of efficacy-based exercise intervention effects on adherence, and may prove useful for researchers in designing interventions with sufficient power to detect statistically significant differences. There is accumulating support for the role of selfefficacy in understanding physical activity in individuals with MS. For example, one study indicated that self-efficacy and impairment both correlated with self-reported physical activity levels, and perceived barriers correlated with self-efficacy in a sample of older adults with MS [9]. Another study reported that enjoyment, social support, and disability had statistically significant direct relationships with self-efficacy, and self-efficacy and enjoyment had statistically significant direct relationships with physical activity in a sample of adults with MS [8]. Consistent with those findings, we found that both self-efficacy and enjoyment were correlated with adherence in the present Table 4 Correlations among baseline self-efficacy and RPE, affect, and enjoyment across the program
1. 2. 3. 4. 5.
Self-efficacy RPE Affect Enjoyment Attendance
1
2
3
4
5
0.25* 0.32* 0.27* 0.36*
/0.08 /0.25* /0.05
0.48* 0.07
0.47*
RPE, ratings of perceived exertion. *Values significant at PB/0.05.
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study. Our findings suggest that further examination of these relationships is warranted to determine whether targeting self-efficacy is a viable strategy for increasing physical activity and exercise behavior in individuals with MS. The adherence effects coupled with the maintenance of well-being, as indicated by satisfaction with life, suggest that the social cognitive context of the exercise environment may be associated with those effects typically reported in exercise studies. More importantly, the self-efficacy intervention appeared to augment the effect of physical activity on perceptions of the exercise experience. That is, individuals with MS assigned to the efficacy enhancement intervention reported working harder (M /13.43; SD /1.88) than the standard care condition (M /12.1; SD /1.81). The higher levels of perceived effort in the efficacy enhancement group were actually closer to the range of intensity prescribed for participants at program onset, and might, therefore, be considered another indicator of better adherence. Moreover, maintaining an intensity level close to or at the level prescribed also suggests a greater likelihood of achieving health benefits associated with exercise intensity. Additionally, social cognitive theory would predict that the affective experience of exercise is likely to be associated with self-efficacy [6,12]. Indeed, those in the efficacy enhancement group reported more positive feeling states as a function of exercise than the control condition. Although these feeling states were not related to overall adherence across groups, they could be interpreted as a rather crude gestalt of positive symptom management, especially in light of the considerable physical demand that even light to moderate intensity exercise places on individuals with MS. Enjoyment, although not differentially influenced by the intervention, was moderately high (ie, M /4.33 on a 1 7 scale) across all subjects, and those who did enjoy physical activity more reported greater adherence. This is an interesting and theoretically important finding. Although enjoyment has been frequently cited as a potential determinant of physical activity behavior in other populations, as well as those with MS [25], there has been little support for this hypothesis. One recent study indicated that enjoyment both directly and indirectly influenced the physical activity levels of individuals with MS [8]. Moreover, if enjoyment is viewed as indicative of positive affect, then such findings are consistent with others who have reported affect to be associated with long-term physical activity behavior in older adults [26]. Perhaps more importantly from a practical and clinical perspective, is the fact that implementing physical activity as primary or secondary prevention of disease rarely results in Multiple Sclerosis 2007; 13: 652 659
an enjoyable experience in the adoption phase. Rather, individuals who are sedentary, or who are weak and easily fatigued due to symptoms associated with a disease state such as MS, are likely to experience physical, psychological, and social discomfort, rather than enjoyment, when embarking on an exercise program. Our findings suggest that structuring the environment to facilitate an enjoyable exercise experience may be important for adherence, and further study of physical activity adherence in MS is warranted. The primary limitation of this study is, of course, the small sample size comprised mainly of females. In spite of aggressive and extensive recruitment, we found it very difficult to attract participants into our study. The many negative symptoms associated with the MS condition, eg, fatigue, balance and coordination loss, are likely to act as deterrents to a health behavior which demands exertion and mobility. These symptoms, coupled with the long-time prevalent message that MS patients should ‘take it easy’ rather than be active, makes for a significant barrier to recruitment. To the sedentary but healthy individual, every aspect of becoming physically active is challenging. To those with MS, this challenge is magnified considerably. Targeted health promotion messages from MS health care providers, which highlight the importance of trying to build physical activity into the lifestyle of the individual with MS, may be an important strategy in this regard. To this end, the use of physically active MS role models to deliver such messages may be equally important. Conducting focus groups with MS patients to identify strategies and incentives to encourage individuals with MS to participate in physical activity interventions would appear another important next step. Additionally, pursuing an intervention strategy that focuses on monitored home-based activity interventions may meet with more success than those interventions that require participants to travel to the exercise venue. The authors gratefully acknowledge April Bell, MS, and Erin Snook, MS, of the University of Illinois at Urban-Champaign and Miles Mettler, PhD, Paul Mettler, DPT, and the staff of the Mettler Center, Champaign-Urbana, IL, for their contributions to this study. Funding for this study was provided, in part, by the National Multiple Sclerosis Society (Grant No. PP1090).
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