Utility of the theory of planned behavior for understanding exercise during breast cancer treatment

Three independent factors predicted adherence in a randomized controlled trial of resistance exercise training among prostate cancer survivors

OBJECTIVE

To examine predictors of adherence in a randomized controlled trial of resistance exercise training (RET) in prostate cancer survivors receiving androgen deprivation therapy.

STUDY DESIGN AND SETTING

A randomized controlled trial conducted at fitness centers in Ottawa and Edmonton, Canada. Prostate cancer survivors (n=155) completed measures of social cognitive variables, quality of life (QOL), behavior, and fitness before being randomized to either an exercise (n=82) or control (n=73) group. The exercise group was asked to perform supervised RET three times per week for 12 weeks.

RESULTS

The exercise group attended 28.2 of the 36 (78.3%) RET sessions. Univariate analyses revealed eight different significant (Ps <.05) predictors of exercise adherence including exercise stage of change, intention, age, QOL, fatigue, subjective norm, leg-press test, and perceived behavioral control. A multivariate analysis indicated that there were three independent predictors of adherence that explained 20.4% of the variance: exercise stage of change (beta=0.26; P=.013), age (beta=-0.22; P=.037), and intention (beta=0.19; P=.073).

CONCLUSION

Exercise adherence in the trial was very good but not optimal. Adherence was predicted by variables from many different categories including social cognitive, QOL, behavioral, fitness, and demographic. These findings may have important implications for maximizing adherence during clinical trials of exercise in prostate cancer survivors.

A prática da atividade física em mulheres submetidas à cirurgia por câncer de mama: percepção de barreiras e benefícios

O exercício físico pós-mastectomia é importante para prevenção da limitação articular, linfedema, alterações posturais, fibrose muscular ou aderência tecidual da área cirúrgica. Objetivo: identificar as crenças a respeito da prática da atividade física, a percepção sobre os benefícios e barreiras à sua realização por um grupo de mulheres submetidas à cirurgia por câncer de mama, segundo o Modelo de Crenças em Saúde. Amostra: 30 mulheres atendidas num serviço especializado em reabilitação de mastectomizadas. Procedimento: aplicou-se um questionário contendo questões relacionadas ao conhecimento e percepções sobre a prática da atividade física, bem como aos benefícios e barreiras à sua realização. Conclusões: o grupo estudado percebeu um conjunto de benefícios sendo a falta de força de vontade a barreira mais mencionada, o conhecimento sobre a importância e a necessidade dos exercícios físicos com a presença de um profissional e o suporte dos familiares foram os incentivos mais referidos pelas mulheres estudadas.

Postoperative education concerning the use of the upper limb, and exercise and treatment of the upper limb: cross-sectional survey of 105 breast cancer patients

In this retrospective survey we investigated the recall of breast cancer patients (n=105) 6 months after the operation concerning postoperative instructions on exercises for shoulder mobility, and instructions for oedema prevention and treatment, upper limb strength training and the use of the upper limb in daily activities. Patients also described the content in their own words and ranked the instructors who had mostly given this education. Operation type and length of hospital stay did not have any effect on the education recalled, but the age of the respondent had some effect (r=-0.23, p<0.05). The Wilcoxon signed ranks test showed that the most commonly reported item was instructions on shoulder movements (P<0.001). Patients reported that they had more instructions for using the upper limb in daily activities than instructions for strength training (P=0.002) and oedema prevention and treatment (P=0.001). Patients own comments were sometimes conflicting: "Use the upper limb as before and you can even lift weights" and "You cannot drive a car or lift a weight over 3 kg for 6 weeks". Over half of the respondents named the physiotherapist or physiotherapy assistant as the person who had given them most of the instructions. A medical doctor was ranked in first place by 19% of the patients. Only half of the patients reported that they had some education after hospitalization. This study suggests that postoperative education of breast cancer patients is inconsistent and insufficient to provide knowledge for independent rehabilitation for future.

Correlates of adherence and contamination in a randomized controlled trial of exercise in cancer survivors: an application of the theory of planned behavior and the five factor model of personality

In this study, we examined correlates of adherence and contamination in a randomized controlled trial (RCT) of exercise in cancer survivors using the theory of planned behavior and the Five Factor Model of personality (FFM). We randomly assigned cancer survivors in group psychotherapy classes to either a waiting-list control group (n = 45) or a home-based, moderate intensity exercise program (n = 51). At baseline, participants completed measures of the theory of planned behavior, the FFM, past exercise, physical fitness, medical variables, and demographics. We then monitored exercise over a 10-week period by weekly self-reports. Hierarchical multiple regression analyses indicated that the independent predictors of overall RCT exercise across both conditions were past exercise (beta = .36, p < .001), assignment to experimental condition (beta = .34, p < .001), sex (beta = .30, p < .001), and intention (beta = .14, p < .10). For exercise adherence in the exercise condition, the independent predictors were sex (beta = .38, p < .01), extraversion (beta = .30, p < .05), normative beliefs (beta = -.27, p < .05), and perceived behavioral control (beta = .23, p < .10). Finally, the independent predictors of exercise contamination in the control condition were past exercise (beta = .70, p < .001), sex (beta = .20, p < .05), and intention (beta = .17, p < .10). We conclude that the correlates of exercise adherence and contamination differ in kind as well as in degree. Explanations for these findings and practical implications for conducting exercise RCTs in this population are offered.

Is the theory of planned behavior a useful framework for understanding exercise adherence during phase II cardiac rehabilitation?

PURPOSE

This study evaluated the theory of planned behavior (TPB) as a framework for understanding exercise adherence during phase II cardiac rehabilitation (CR).

METHODS

A total of 215 patients completed a baseline questionnaire that included the TPB constructs and past exercise. Exercise adherence was measured via program attendance during phase II CR.

RESULTS

Hierarchic regression analyses indicated that attitude, subjective norm, and perceived behavioral control (PBC) explained 30% of the variance in exercise intention, with attitude, subjective norm, and PBC each making significant unique contributions to intention. Furthermore, exercise intention explained 12% of the variance in exercise adherence. Finally, the behavioral, normative, and control beliefs provided novel information concerning why patients in phase II CR hold certain attitudes, subjective norms, PBC, and exercise intentions.

CONCLUSION

Results of the present study provide evidence that the TPB is a useful framework for understanding exercise intentions and adherence during phase II CR.

Framework PEACE: an organizational model for examining physical exercise across the cancer experience

The primary purpose of this article is to provide a framework for organizing research on physical exercise and cancer control. A secondary purpose is to use this framework to provide an overview of the extant literature and to offer directions forr future research. The proposed framework, entitled Physical Exercise Across the Cancer Experience (PEACE), divides the cancer experience into 6 time periods: 2 prediagnosis (i.e., prescreening and screening/diagnosis) and 4 postdiagnosis (i.e., pretreatment, treatment, posttreatment, and resumption). Based on these time periods, 8 general cancer control outcomes are highlighted. Two cancer control outcomes occur prediagnosis (i.e., prevention and detection), and 6 occur postdiagnosis (i.e., buffering, coping, rehabilitation, health promotion, palliation, and survival). An overview of the physical exercise literature indicates that only I time period (i.e., prescreening) and cancer control outcome (i.e., prevention) has received significant research attention. Some time periods (i.e., treatment and resumption) and cancer control outcomes (i.e., coping and health promotion) have received modest research attention, whereas other time periods (i.e., screening/diagnosis, pretreatment, and posttreatment) and cancer control outcomes (i.e., detection, buffering, rehabilitation, palliation, and survival) have received only minimal attention. It is hoped that Framework PEACE will stimulate a more comprehensive and in-depth inquiry into the role of physical exercise in cancer control.

Integrating behavior change theory into geriatric case management practice

Case management practices have continued to grow despite a lack of clear evidence of their efficacy. With the expanding segment of the elderly population, there is a critical need to develop and identify programs that will address the many needs of the aging. Geriatric Case Management has been the avenue selected by many health care providers to address these issues, focusing on maintaining health status and improving linkages with medical and community resources. Studies testing the effectiveness of these models have failed to demonstrate their effectiveness in reducing depression, reducing acute care service use, and improving or maintaining health status. The Geriatric Case Management models presented in these lack an evidence-based, theoretical framework that provides definition and direction for case management practice. This article introduces behavior change theories as a method of structuring and delineating the case management intervention. The Transtheoretical Model and the Theory of Planned Behavior are discussed and methods of integrating these theories into practice are discussed.

Determinants of exercise intention and behavior in survivors of breast and prostate cancer: an application of the theory of planned behavior

The purpose of this study was to evaluate the theory of planned behavior as a framework for understanding exercise intention and behavior in survivors of breast and prostate cancer. Participants were 83 survivors of breast and 46 survivors of prostate cancer who were diagnosed within the previous 4 years and had completed treatment. Each participant completed a mailed self-administered questionnaire that assessed exercise during the previous week, demographic and medical variables, and the theory of planned behavior. For survivors of breast cancer, regression analyses indicated that attitude, subjective norm, and perceived behavioral control explained 45% of the variance in exercise intention with attitude, subjective norm, and perceived behavioral control each uniquely contributing to intention. Furthermore, exercise intention explained 30% of the variance in exercise behavior; however, perceived behavioral control added no unique variance. For survivors of prostate cancer, attitudes, subjective norm, and perceived behavioral control explained 36% of the variance in exercise intention, but only perceived behavioral control made a significant unique contribution. Furthermore, intention explained 36% of the variance in exercise behavior; however, perceived behavioral control added no unique variance. Results suggest that nurses may use the theory of planned behavior as a model for understanding the determinants of exercise intentions and behavior in survivors of breast and prostate cancer.

Motivation to modify lifestyle risk behaviors in women treated for breast cancer

OBJECTIVE

To determine motivators of health behaviors (relevant to risk for chronic disease and cancer recurrence) after a cancer diagnosis.

PATIENTS AND METHODS

Eighty-six women who had been treated for breast cancer (mean age, 54.8 years; median time since diagnosis, 23.5 months) participated in this cross-sectional study (1997-1998). Respondents completed a questionnaire assessing overweight or obesity status, dietary fat intake, energy expenditure, motivational readiness for exercise and weight loss, and variables associated with readiness for exercise adoption and weight loss.

RESULTS

Forty-six women (54%) were overweight or obese, and 47 women (55%) reported dietary fat intake of 30% or higher. Sixty-one women (72%) were in action/ maintenance stages for exercise adoption. A majority believed that diet and exercise can change the course of cancer. Overweight and obese women in the sample were more likely to be in early stages of motivational readiness for weight loss, and they reported significantly lower exercise self-efficacy and lower eating self-efficacy than their nonoverweight peers. However, they endorsed more benefits associated with weight loss than the nonoverweight subgroup. Thirty-three women (39%) reported both a low-fat diet and exercising at recommended levels.

CONCLUSIONS

Only a minority of respondents reported consuming a diet low in fat and exercising at recommended levels, which suggests a need to improve both diet and exercise behaviors among women treated for breast cancer. Overweight and obese women reported low self-efficacy for exercise and eating, suggesting that interventions should focus on increasing self-efficacy for behavior change.

Personality and exercise participation across the breast cancer experience

The purpose of this study was to investigate the relationship between personality and exercise participation across the breast cancer experience. Based on the Five-Factor Model and previous exercise research, it was hypothesized that high scores of extraversion (E) and conscientiousness (C), and low scores of neuroticism (N) would discriminate exercise stage during and following cancer treatment as well as changes in exercise stage across the cancer experience (i.e. from prediagnosis through treatment to posttreatment). Participants were 175 non-metastatic breast cancer survivors who completed a mailed questionnaire that assessed demographic and medical information, personality (the NEO-Five Factor Inventory), and exercise stage recalled for three time periods (prediagnosis, during treatment, and posttreatment). Multivariate analysis of variance showed differences in personality based on exercise stage both during cancer treatment and posttreatment and also for exercise pattern across the cancer experience. Univariate F-tests and post hoc analyses identified N, E, and C as the key personality dimensions. N was associated with earlier exercise stages and a maladaptive exercise pattern whereas E and C were associated with more advanced exercise stages and adaptive exercise patterns. It was concluded that personality may be an important determinant of exercise following breast cancer diagnosis.

Exercise adherence in breast cancer survivors training for a dragon boat race competition: a preliminary investigation

Recent research has applied the theory of planned behavior (TPB) to understanding exercise after a cancer diagnosis, but studies are few and have been limited by retrospective designs, self-report measures of exercise and varied results. In the present study, we extended this research by using a prospective design and an objective measure of exercise adherence. Participants were a convenience sample of 24 breast cancer survivors attending a twice weekly, 12-week training program in preparation for a dragon boat race competition. Participants completed a baseline questionnaire that assessed demographic and medical variables, past exercise, and the TPB (i.e. beliefs, subjective norm, attitude, perceived behavioral control and intention). Program attendance was monitored over a 12-week period by the class instructor. Overall, participants attended 66% of the training sessions. Multiple regression analyses indicated that: (a) intention was the sole determinant of program attendance and explained 35% of the variance; (b) the TPB constructs explained 49% of the variance in intention with subjective norm being the most important determinant; and (c) the key underlying beliefs were support from physician, spouse, and friends, and confidence in being able to attend the training class when having limited time, no one to exercise with, fatigue, and other health problems. Based on this preliminary study, it was concluded that the TPB may provide a good framework on which to base interventions designed to promote exercise in breast cancer survivors.