Analyzing theoretical mechanisms of physical activity behavior change in breast cancer survivors: results from the activity promotion (ACTION) trial.

BACKGROUND: We previously reported that a physical activity (PA) behavior change intervention based on the theory of planned behavior (TPB) increased PA and quality of life in breast cancer survivors. PURPOSE: To examine the effects of our interventions on TPB variables and to determine if PA at 12 weeks follow-up was mediated by TPB variables at 4 weeks. METHODS: Breast cancer survivors (N = 377) were randomly assigned to receive either a standard public health recommendation for PA (SR group), a step pedometer alone, or one of two TPB-based behavior change interventions consisting of print materials (alone or combined with a step pedometer). For the purpose of this study, we compared the two TPB-based intervention groups (INT group) to the SR group. RESULTS: Compared to the SR group, the INT group reported more favorable changes in instrumental attitude (mean difference = 0.13; 95% CI = -0.01 to 0.23; d = 0.19; p = 0.077), intention (mean difference = 0.33; 95% CI = 0.10 to 0.56; d = 0.33; p = 0.006), and planning (mean difference = 0.39; 95% CI = 0.04 to 0.73; d = 0.26; p = 0.027). Mediation analyses indicated that both planning and intention partially mediated the effects of the intervention on PA at 12 weeks. CONCLUSIONS: Our TPB-based behavior change intervention resulted in small improvements in the TPB constructs that partially mediated the effects of our intervention on PA behavior. Additional research with the TPB is warranted.

Effects of aerobic and resistance exercise in breast cancer patients receiving adjuvant chemotherapy: a multicenter randomized controlled trial.

PURPOSE: Breast cancer chemotherapy may cause unfavorable changes in physical functioning, body composition, psychosocial functioning, and quality of life (QOL). We evaluated the relative merits of aerobic and resistance exercise in blunting these effects. PATIENTS AND METHODS: We conducted a multicenter randomized controlled trial in Canada between 2003 and 2005 that randomly assigned 242 breast cancer patients initiating adjuvant chemotherapy to usual care (n = 82), supervised resistance exercise (n = 82), or supervised aerobic exercise (n = 78) for the duration of their chemotherapy (median, 17 weeks; 95% CI, 9 to 24 weeks). Our primary end point was cancer-specific QOL assessed by the Functional Assessment of Cancer Therapy-Anemia scale. Secondary end points were fatigue, psychosocial functioning, physical fitness, body composition, chemotherapy completion rate, and lymphedema. RESULTS: The follow-up assessment rate for our primary end point was 92.1%, and adherence to the supervised exercise was 70.2%. Unadjusted and adjusted mixed-model analyses indicated that aerobic exercise was superior to usual care for improving self-esteem (P = .015), aerobic fitness (P = .006), and percent body fat (adjusted P = .076). Resistance exercise was superior to usual care for improving self-esteem (P = .018), muscular strength (P < .001), lean body mass (P = .015), and chemotherapy completion rate (P = .033). Changes in cancer-specific QOL, fatigue, depression, and anxiety favored the exercise groups but did not reach statistical significance. Exercise did not cause lymphedema or adverse events. CONCLUSION: Neither aerobic nor resistance exercise significantly improved cancer-specific QOL in breast cancer patients receiving chemotherapy, but they did improve self-esteem, physical fitness, body composition, and chemotherapy completion rate without causing lymphedema or significant adverse events.

Randomized controlled trial of the effects of print materials and step pedometers on physical activity and quality of life in breast cancer survivors.

PURPOSE: To determine the effects of breast cancer-specific print materials and step pedometers on physical activity (PA) and quality of life (QoL) in breast cancer survivors. PATIENTS AND METHODS: Breast cancer survivors (N = 377) were randomly assigned to receive one of the following: a standard public health recommendation for PA, previously developed breast cancer-specific PA print materials, a step pedometer, or a combination of breast cancer-specific print materials and step pedometers. The primary outcome was self-reported moderate/vigorous PA minutes per week. Secondary outcomes were QoL (Functional Assessment of Cancer Therapy-Breast), fatigue, self-reported brisk walking, and objective step counts. Assessments were conducted at baseline and postintervention (12 weeks). RESULTS: Attrition was 10.3% (39 of 377). On the basis of linear mixed-model analyses, PA increased by 30 minutes/week in the standard recommendation group compared with 70 minutes/week in the print material group (mean difference, 39 minutes/week; 95% CI = -10 to 89; d = 0.25; P = .117), 89 minutes/week in the pedometer group (mean difference, 59 minutes/week; 95% CI, 11 to 108; d = 0.38; P = .017), and 87 minutes/week in the combined group (mean difference, 57 minutes/week; 95% CI, 8 to 106; d = 0.37; P = .022). For brisk walking minutes/week, all three intervention groups reported significantly greater increases than the standard recommendation group. The combined group also reported significantly improved QoL (mean difference, 5.8; 95% CI, 2.0 to 9.6; d = 0.33; P = .003) and reduced fatigue (mean difference, 2.3; 95% CI, 0.0 to 4.7; d = 0.25; P = .052) compared with the standard recommendation group. CONCLUSION: Breast cancer-specific PA print materials and pedometers may be effective strategies for increasing PA and QoL in breast cancer survivors. A combined approach appears to be optimal. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00221221

Understanding the determinants of exercise intentions in multiple myeloma cancer survivors: an application of the theory of planned behavior.

The purpose of this study was to examine the demographic, medical, and social cognitive determinants of exercise intentions in a population-based sample of multiple myeloma cancer survivors. Using a cross-sectional survey, 70 multiple myeloma cancer survivors completed a questionnaire that assessed their medical and demographic characteristics, past exercise behavior, and social cognitive exercise beliefs using the theory of planned behavior. Seventy participants provided valuable data. Descriptive statistics indicated that participants had quite positive instrumental attitude, intentions, and subjective norms and moderate levels of perceived behavioral control and affective attitudes for exercise. Forced entry multiple regression showed that the theory of planned behavior explained 43% of the variance in exercise intentions. Instrumental attitude and perceived behavioral control were both independent predictors of exercise intentions. No demographic or medical variable moderated the association between the theory of planned behavior constructs and exercise intentions. The results of the present investigation support the growing body of evidence confirming the utility of the theory of planned behavior to understand the salient determinants of exercise in cancer survivors. Knowledge gained from this study provides important information to oncology practitioners who are responsible for delivering supportive care interventions, including exercise, to patients diagnosed with multiple myeloma.

A longitudinal study of exercise barriers in colorectal cancer survivors participating in a randomized controlled trial.

BACKGROUND: The Colorectal Cancer and Home-Based Physical Exercise (CAN-HOPE) trial compared the effects of a 16-week home-based exercise program to usual care on quality of life in colorectal cancer survivors. PURPOSE: In this study, we report the weekly exercise barriers from the exercise group. METHODS: Participants randomized to the exercise group (N = 69) were asked to report their exercise on a weekly basis by telephone. Those participants not achieving the minimum weekly exercise prescription (3 times per week of 30 min of moderate intensity exercise) were asked for a primary exercise barrier. RESULTS: We obtained 1,073 (97.2%) weeks of adherence data out of a possible 1,104 (i.e., 69 x 16). Participants did not meet the minimum exercise prescription in 39.2% (421/1,073) of the weeks. We obtained an exercise barrier in 83.8% (353/421) of these cases. Overall, participants reported 37 different exercise barriers; the three most common were lack of time/too busy, nonspecific treatment side effects, and fatigue. The top 7 to 10 barriers accounted for 70% to 80% of all missed exercise weeks. CONCLUSIONS: These findings may have utility for promoting exercise in this population both inside and outside of clinical trials.

Differences in quality of life between non-Hodgkin's lymphoma survivors meeting and not meeting public health exercise guidelines.

The primary purpose of this study was to examine differences in quality of life (QoL) between non-Hodgkin's lymphoma (NHL) survivors meeting and not meeting public health exercise guidelines. A secondary purpose was to examine exercise behavior changes across three distinct cancer-related time periods (i.e. prediagnosis, on treatment and off treatment). Using a retrospective survey design, 438 NHL survivors residing in Alberta, Canada completed a mailed questionnaire that assessed self-reported exercise prediagnosis, on treatment and off treatment, and current QoL. Descriptive analyses indicated that 33.8, 6.5 and 23.7% of NHL survivors met public health exercise guidelines during prediagnosis, on treatment, and off treatment time periods, respectively. Multivariate analyses of variance indicated that NHL survivors meeting public health exercise guidelines during postdiagnosis time periods had higher current QoL scores than NHL survivors not meeting guidelines. QoL difference scores between the two groups met proposed standards for clinically important differences. Multivariate analyses also indicated significant differences in exercise behavior across the three cancer-related time periods (all p's<0.01). These analyses were unchanged after statistically controlling for important medical and demographic variables. The results of this study provide evidence that NHL survivors meeting public health exercise guidelines on and off treatment reported higher current QoL than those survivors not meeting guidelines. These findings corroborate research examining exercise behavior in other cancer survivor groups and provide preliminary data to support a randomized controlled trial on exercise and QoL in this population.

Association between exercise and quality of life in multiple myeloma cancer survivors.

GOALS OF THE WORK: The goal of this study was to examine the association between exercise and quality of life (QOL) in multiple myeloma cancer survivors. PATIENTS AND METHODS: Using a retrospective design, 156 multiple myeloma cancer survivors were mailed a questionnaire that assessed self-reported exercise behavior over three periods (prediagnosis, active treatment, and off-treatment) and QOL. MAIN RESULTS: The response rate was 56% (88/ 156). Descriptive analyses indicated that 6.8% and 20.4% of survivors met national exercise guidelines during active and off-treatment periods, respectively. Exercise during active treatment and off-treatment were positively associated with overall QOL and all subdomains of QOL (all P<0.05) except physical wellbeing. CONCLUSIONS: A low percentage of multiple myeloma cancer survivors are exercising regularly either during active or off-treatment periods. Survivors who report more exercise during these periods also report higher QOL. These findings suggest that a randomized controlled trial is warranted.

Exercise issues in older cancer survivors.

Older cancer survivors experience the combined deleterious effects associated with aging and a cancer diagnosis. The purpose of the present paper is to review the potential role of physical exercise in attenuating the effects of cancer and its treatments in older cancer survivors. Noting the limited direct research on exercise in older cancer survivors, we review the literature on: (a) older adults in general; and (b) cancer survivors in general. We conclude that although there is limited direct evidence on the benefits of exercise in older cancer survivors, there is compelling evidence of the benefits of exercise in cancer survivors in general and other older populations. We also conclude that exercise adherence will be a significant challenge in this population. Based on this evidence, we tentatively recommend exercise to older cancer survivors using the American College of Sports Medicine's [Med Sci Sports Exerc 30 (6) (1998) 992] guidelines for older adults in general. Finally, we offer future research directions that will provide important evidence needed to guide clinical decisions about exercise in older cancer survivors.