The LISA randomized trial of a weight loss intervention in postmenopausal breast cancer.

Obesity has been associated with poor breast cancer (BC) outcomes. We investigated whether a standardized, telephone-based weight loss lifestyle intervention in the adjuvant setting would impact BC outcomes. We conducted a multicenter trial randomizing women 1:1 to mail-based educational material alone (control) or combined with a standardized, telephone-based lifestyle intervention that focused on diet, physical activity, and behavior and involved 19 calls over 2 years to achieve up to 10% weight loss. In all, 338 (of 2150 planned) T1-3, N0-3, M0 hormone receptor positive BC patients with body mass index (BMI) ≥24 kg/m2 receiving adjuvant letrozole were randomized (enrolment ended due to funding loss). The primary outcome was disease-free survival (DFS); secondary outcome was Overall Survival (OS). At 8 years' median follow-up, in a planned analysis, DFS and OS were compared using the Kaplan-Meier method. Baseline BMI and other characteristics were similar between study arms. In all, 22 of 171 (12.9%) in the lifestyle intervention arm versus 30 of 167 (18.0%) in the education had DFS events; the hazard ratio (HR) was 0.71 (95% confidence interval [CI]: 0.41-1.24, p = 0.23). Although loss of funding reduced sample size, we view these hypothesis generating results as compatible with our hypothesis of a potential beneficial effect of a lifestyle intervention on DFS. They provide support for completion of ongoing randomized controlled trials of the effect of lifestyle interventions in BC outcomes.

Impact of resistance and aerobic exercise on sarcopenia and dynapenia in breast cancer patients receiving adjuvant chemotherapy: a multicenter randomized controlled trial.

The purpose of this study was to conduct an exploratory analysis of the START examining the effects of resistance exercise training (RET) and aerobic exercise training (AET) on sarcopenia, dynapenia, and associated quality of life (QoL) changes in breast cancer (BC) patients receiving adjuvant chemotherapy. Participants were randomized to usual care (UC) (n = 70), AET (n = 64), or RET (n = 66) for the duration of chemotherapy. Measures of sarcopenia [skeletal muscle index (SMI)] and dynapenia [upper extremity (UE) and lower extremity (LE) muscle dysfunction (MD)] were normalized relative to age-/sex-based clinical cut-points. QoL was assessed by the Functional Assessment of Cancer Therapy-Anemia (FACT-An) scales. At baseline, 25.5 % of BC patients were sarcopenic and 54.5 % were dynapenic with both conditions associated with poorer QoL. ANCOVAs showed significant differences favoring RET over UC for SMI (0.32 kg/m(2); p = 0.017), UE-MD (0.12 kg/kg; p < 0.001), and LE-MD (0.27 kg/kg; p < 0.001). Chi-square analyses revealed significant effects of RET, compared to UC/AET combined, on reversing sarcopenia (p = 0.039) and dynapenia (p = 0.019). The reversal of sarcopenia was associated with clinically relevant improvements in the FACT-An (11.7 points [95 % confidence interval (CI) -4.2 to 27.6]), the Trial Outcome Index-Anemia (10.0 points [95 % CI -4.0 to 24.1]), and fatigue (5.3 points [95 % CI -1.5 to 12.1]). Early-stage BC patients initiating adjuvant chemotherapy have higher than expected rates of sarcopenia and dynapenia which are associated with poorer QoL. RET during adjuvant chemotherapy resulted in the reversal of both sarcopenia and dynapenia; however, only the reversal of sarcopenia was associated with clinically meaningful improvements in QoL.

Motivation for Different Types and Doses of Exercise During Breast Cancer Chemotherapy: a Randomized Controlled Trial.

BACKGROUND: Exercise is beneficial for breast cancer patients during chemotherapy, but their motivation to perform different types and doses of exercise is unknown. PURPOSE: The purpose of this study was to examine the anticipated and experienced motivation of breast cancer patients before and after three different exercise programs during chemotherapy. METHODS: Breast cancer patients initiating chemotherapy (N = 301) were randomized to a standard dose of 25-30 min of aerobic exercise, a higher dose of 50-60 min of aerobic exercise, or a combined dose of 50-60 min of aerobic and resistance exercise. Patient preference and motivational outcomes from the theory of planned behavior (i.e., perceived benefit, enjoyment, support, difficulty, and motivation) were assessed before and after the interventions. RESULTS: At pre-randomization, breast cancer patients were significantly (p < 0.001) more likely to prefer the combined program (80.1 %); however, after the interventions there was a significant (p < 0.001) increase in the number of patients preferring the high volume program and having no preference. At pre-randomization, breast cancer patients anticipated more favorable motivational outcomes for the combined program and less favorable motivational outcomes for the high volume program (all p < 0.001). After the interventions, the motivational outcomes experienced exceeded the anticipated motivational outcomes significantly more in the high volume group than the standard or combined groups. CONCLUSIONS: Anticipated motivational outcomes for different types and doses of exercise during chemotherapy varied considerably at pre-randomization, but the motivational outcomes experienced after the three interventions were similar. Clinicians can recommend any of the three exercise interventions to breast cancer patients knowing that positive motivational outcomes will result. Clinicaltrials.gov identifier: NCT00249015 .

Predictors of adherence to different types and doses of supervised exercise during breast cancer chemotherapy.

BACKGROUND: Exercise is beneficial for breast cancer patients during chemotherapy but adherence to different types and doses of exercise is a challenge. The purpose of this study was to examine predictors of adherence to different types and doses of exercise during breast cancer chemotherapy in a multicenter randomized controlled trial. METHODS: Breast cancer patients in Edmonton, Vancouver, and Ottawa, Canada receiving chemotherapy (N = 301) were randomized to a standard dose of 25-30 minutes of aerobic exercise (STAN), a higher dose of 50-60 minutes of aerobic exercise (HIGH), or a higher dose of 50-60 minutes of combined aerobic and resistance exercise (COMB). Predictors included demographic, medical, fitness, and quality of life variables. Exercise adherence was measured as the percentage of supervised exercise sessions completed. RESULTS: Overall adherence to the supervised exercise sessions was 73% (SD = 24%). In a multivariate regression model, six independent predictors explained 26.4% (p < 0.001) of the variance in exercise adherence. Higher exercise adherence was achieved by breast cancer patients in Vancouver (p < 0.001), with fewer endocrine symptoms (p = 0.009), randomized to STAN (p = 0.009), with fewer exercise limitations (p = 0.009), receiving shorter chemotherapy protocols (p = 0.015), and with higher VO2peak (p = 0.017). Disease stage (p for interaction = 0.015) and body mass index (p for interaction = 0.030) interacted with group assignment to predict adherence. For disease stage, patients with stage I/IIa disease adhered equally well to all three exercise interventions whereas patients with stage IIb/III disease adhered better to the STAN intervention than the two higher dose exercise interventions. For body mass index, healthy weight patients adhered equally well to all three exercise interventions whereas overweight patients adhered best to STAN and worst to COMB; and obese patients adhered best to STAN and worst to HIGH. CONCLUSIONS: Determinants of exercise adherence in breast cancer patients receiving chemotherapy are multidisciplinary and may vary by the exercise prescription.

Randomized trial of a telephone-based weight loss intervention in postmenopausal women with breast cancer receiving letrozole: the LISA trial.

PURPOSE: Obesity is associated with poor outcomes in women with operable breast cancer. Lifestyle interventions (LIs) that help women reduce their weight may improve outcomes. PATIENTS AND METHODS: We conducted a multicenter randomized trial comparing mail-based delivery of general health information alone or combined with a 24-month standardized, telephone-based LI that included diet (500 to 1,000 kcal per day deficit) and physical activity (150 to 200 minutes of moderate-intensity physical activity per week) goals to achieve weight loss (up to 10%). Women receiving adjuvant letrozole for T1-3N0-3M0 breast cancer with a body mass index (BMI) ≥ 24 kg/m(2) were eligible. Weight was measured in the clinic, and self-report physical activity, quality-of-life (QOL), and diet questionnaires were completed. The primary outcome was disease-free survival. Accrual was terminated at 338 of 2,150 planned patients because of loss of funding. RESULTS: Mean weight loss was significantly (P < .001) greater in the LI arm versus the comparison arm (4.3 v 0.6 kg or 5.3% v 0.7% at 6 months and 3.1 v 0.3 kg or 3.6% v 0.4% at 24 months) and occurred consistently across strata (BMI 24 to < 30 v ≥ 30 kg/m(2); prior v no prior adjuvant chemotherapy). Weight loss was greatest in those with higher baseline levels of moderate-intensity physical activity or improvement in QOL. Hospitalization rates and medical events were similar. CONCLUSION: A telephone-based LI led to significant weight loss that was still evident at 24 months, without adverse effects on QOL, hospitalizations, or medical events. Adequately powered randomized trials with cancer end points are needed.

Effects of exercise during adjuvant chemotherapy on breast cancer outcomes.

UNLABELLED: Observational studies suggest that physical activity after a breast cancer diagnosis is associated with improved cancer outcomes; however, no randomized data are available. Here, we report an exploratory follow-up of cancer outcomes from the Supervised Trial of Aerobic versus Resistance Training (START). METHODS: The START was a Canadian multicenter trial that randomized 242 breast cancer patients between 2003 and 2005 to usual care (n = 82), supervised aerobic (n = 78), or resistance (n = 82) exercise during chemotherapy. The primary end point for this exploratory analysis was disease-free survival (DFS). Secondary end points were overall survival, distant DFS, and recurrence-free interval. The two exercise arms were combined for analysis (n = 160), and selected subgroups were explored. RESULTS: After a median follow-up of 89 months, there were 25/160 (15.6%) DFS events in the exercise groups and 18/82 (22.0%) in the control group. Eight-year DFS was 82.7% for the exercise groups compared with 75.6% for the control group (HR, 0.68; 95% confidence interval (CI), 0.37-1.24; log-rank, P = 0.21). Slightly stronger effects were observed for overall survival (HR, 0.60; 95% CI, 0.27-1.33; log-rank, P = 0.21), distant DFS (HR, 0.62; 95% CI, 0.32-1.19; log-rank, P = 0.15), and recurrence-free interval (HR, 0.58; 95% CI, 0.30-1.11; Gray test, P = 0.095). Subgroup analyses suggested potentially stronger exercise effects on DFS for women who were overweight/obese (HR, 0.59; 95% CI, 0.27-1.27), had stage II/III cancer (HR, 0.61; 95% CI, 0.31-1.20), estrogen receptor-positive tumors (HR, 0.58; 95% CI, 0.26-1.29), human epidermal growth factor receptor 2-positive tumors (HR, 0.21; 95% CI, 0.04-1.02), received taxane-based chemotherapies (HR, 0.46; 95% CI, 0.19-1.15), and ≥85% of their planned chemotherapy (HR, 0.50; 95% CI, 0.25-1.01). CONCLUSIONS: This exploratory follow-up of the START provides the first randomized data to suggest that adding exercise to standard chemotherapy may improve breast cancer outcomes. A definitive phase III trial is warranted.

A multicenter randomized trial of the effects of exercise dose and type on psychosocial distress in breast cancer patients undergoing chemotherapy.

BACKGROUND: Exercise may improve psychosocial distress in patients with cancer; however, few studies have examined the effects of different types or doses of exercise, or whether exercise effects are related to baseline depression levels. METHODS: In a multicenter trial in Canada, we randomized 301 patients with breast cancer initiating chemotherapy to thrice weekly, supervised exercise consisting of either a standard dose of 25 to 30 minutes of aerobic exercise (STAN; n = 96), a higher dose of 50 to 60 minutes of aerobic exercise (HIGH; n = 101), or a combined dose of 50 to 60 minutes of aerobic and resistance exercise (COMB; n = 104). The primary endpoint was depression assessed by the Center for Epidemiological Studies-Depression scale at baseline, twice during chemotherapy, and postchemotherapy. Secondary endpoints were anxiety, perceived stress, and self-esteem. RESULTS: Repeated measures ANOVA indicated that neither HIGH [mean difference = -0.9; 95% confidence interval (CI), +0.0 to -1.8; P = 0.061] nor COMB (mean difference = -0.4; 95% CI, +0.5 to -1.3; P = 0.36) was superior to STAN for managing depressive symptoms. In a planned subgroup analysis, there was a significant interaction with baseline depression levels (P interaction = 0.027) indicating that COMB and HIGH were effective for managing depressive symptoms in patients with clinical levels of depressive symptoms at baseline. CONCLUSIONS: Compared with a standard volume of aerobic exercise, higher volumes of exercise did not help manage depressive symptoms in unselected patients with breast cancer receiving chemotherapy, but they were effective in patients with clinical levels of depressive symptoms at baseline. IMPACT: A phase III exercise trial targeting depressed patients with breast cancer is warranted.

Effects of exercise dose and type on sleep quality in breast cancer patients receiving chemotherapy: a multicenter randomized trial.

To examine the effects of different doses and types of exercise on sleep quality in breast cancer patients receiving chemotherapy. A multicenter trial in Canada randomized 301 breast cancer patients between 2008 and 2011 to thrice weekly, supervised exercise during chemotherapy consisting of either a standard dose of 25-30 min of aerobic exercise (STAN; n = 96), a higher dose of 50-60 min of aerobic exercise (HIGH; n = 101), or a combined dose of 50-60 min of aerobic and resistance exercise (COMB; n = 104). The secondary sleep outcomes in the trial were assessed by the Pittsburgh Sleep Quality Index (PSQI) at baseline, twice during chemotherapy, and postchemotherapy. We analyzed the global PSQI and the component scores. Repeated measures analyses of variance indicated that the HIGH group was statistically superior to the STAN group for global sleep quality (mean group difference = -0.90; 95 % CI -0.05 to -1.76; p = 0.039) as well as subjective sleep quality (p = 0.028) and sleep latency (p = 0.049). The COMB group was borderline statistically superior to the STAN group for global sleep quality (mean group difference = -0.76; 95 % CI +0.11 to -1.62; p = 0.085) as well as sleep duration (p = 0.051); and statistically superior for sleep efficiency (p = 0.040), and percentage of poor sleepers (p = 0.045). Compared to a standard volume of aerobic exercise, higher volumes of both aerobic and combined exercise improved some aspects of sleep quality during breast cancer chemotherapy. Exercise may be an attractive option to manage sleep dysfunction in cancer patients during chemotherapy.

Effects of exercise dose and type during breast cancer chemotherapy: multicenter randomized trial.

BACKGROUND: Exercise improves physical functioning and symptom management during breast cancer chemotherapy, but the effects of different doses and types of exercise are unknown. METHODS: A multicenter trial in Canada randomized 301 breast cancer patients to thrice-weekly supervised exercise during chemotherapy consisting of either a standard dose of 25 to 30 minutes of aerobic exercise (STAN; n = 96), a higher dose of 50 to 60 minutes of aerobic exercise (HIGH; n = 101), or a combined dose of 50 to 60 minutes of aerobic and resistance exercise (COMB; n = 104). The primary endpoint was physical functioning assessed by the Medical Outcomes Survey-Short Form (SF)-36. Secondary endpoints were other physical functioning scales, symptoms, fitness, and chemotherapy completion. All statistical tests were linear mixed model analyses, and the P values were two-sided. RESULTS: Follow-up assessment of patient-reported outcomes was 99.0%. Adjusted linear mixed-model analyses showed that neither HIGH (+0.8; 95% confidence interval [CI] = -0.8 to 2.4; P = .30) nor COMB (+0.5; 95% CI = -1.1 to 2.1; P = .52] were superior to STAN for the primary outcome. In secondary analyses not adjusted for multiple comparisons, HIGH was superior to STAN for the SF-36 physical component summary (P = .04), SF-36 bodily pain (P = .02), and endocrine symptoms (P = .02). COMB was superior to STAN for endocrine symptoms (P = .009) and superior to STAN (P < .001) and HIGH (P < .001) for muscular strength. HIGH was superior to COMB for the SF-36 bodily pain (P = .04) and aerobic fitness (P = .03). No differences emerged for body composition or chemotherapy completion. CONCLUSIONS: A higher volume of aerobic or combined exercise is achievable and safe during breast cancer chemotherapy and may manage declines in physical functioning and worsening symptoms better than standard volumes.

Age and androgen-deprivation therapy on exercise outcomes in men with prostate cancer.

PURPOSE: The purpose of this study is to examine the effects of age (≤ 65 years or >65 years) and androgen-deprivation therapy (ADT, presence or absence) as factors that may predict changes in body composition and fitness following a 24-week exercise program in prostate cancer patients. METHODS: One hundred twenty-one men were randomly allocated to either: (1) aerobic exercise (AE), (2) resistance exercise (RE), or (3) usual care (UC). Body composition was assessed by DXA. Aerobic fitness was assessed through a maximal treadmill test. Muscular strength was assessed by leg extension and bench press using the eight-repetition maximum test. Responses were compared between younger (≤ 65 years) and older (> 65 years) patients with or without ADT. RESULTS: There did not appear to be an interaction between age and ADT on body composition or fitness, nor were there any significant changes in body composition for participants ≤ 65 years. In participants aged >65 years, lean mass decreased in AE (p = 0.013) and UC (p = 0.006), but was preserved in RE. In participants receiving ADT, there was a decrease in lean mass in AE (p = 0.003) and UC (p < 0.001) but not in RE. The non-ADT group did not show any changes in body composition but did show improvements in muscular fitness following resistance training (p < 0.001). CONCLUSION: Changes in body composition and physical fitness following a 24-week exercise program in men with prostate cancer are not influenced by age and/or ADT. Resistance training appears to attenuate the age-related decrease in lean mass and increase in body fat in older patients with prostate cancer and those receiving ADT.

Hemoglobin and aerobic fitness changes with supervised exercise training in breast cancer patients receiving chemotherapy.

BACKGROUND: Aerobic exercise training (AET) is known to increase RBC production; however, this has not been evaluated in breast cancer patients undergoing adjuvant chemotherapy. The purpose of this study was to examine the changes in hemoglobin (Hb) levels in the Supervised Trial of Aerobic versus Resistance Training (START) and to determine its association with changes in VO(2peak). METHODS: Two hundred and forty-two breast cancer patients initiating chemotherapy were randomized to usual care (n = 82), resistance exercise (RET, n = 82), or AET (n = 78) groups for the duration of their chemotherapy (median, 17 weeks). Supervised exercise was thrice weekly based on standard AET and RET prescriptions. Aerobic fitness (VO(2peak)) and Hb concentration were measured at baseline and end of chemotherapy. RESULTS: Regardless of the exercise group, Hb declined over the course of chemotherapy (13.4 ± 10.0 to 11.8 ± 11.5 g/dL, P < 0.01). Both AET and RET groups had significant, moderate correlations between the change in VO(2peak) and Hb (AET: r = 0.49, P < 0.001; RET: r = 0.39, P = 0.001). CONCLUSION: The results indicate that regular exercise does not protect against the decline in Hb associated with chemotherapy in breast cancer patients, but resulted in a stronger association between Hb and VO(2peak). IMPACT: Even with the chemotherapy-induced decline in Hb, breast cancer patients can maintain their aerobic capacity by participating in regular aerobic exercise. Further studies are required to determine safe intensity levels that may stimulate the maintenance of Hb levels in breast cancer patients.

American College of Sports Medicine roundtable on exercise guidelines for cancer survivors.

Early detection and improved treatments for cancer have resulted in roughly 12 million survivors alive in the United States today. This growing population faces unique challenges from their disease and treatments, including risk for recurrent cancer, other chronic diseases, and persistent adverse effects on physical functioning and quality of life. Historically, clinicians advised cancer patients to rest and to avoid activity; however, emerging research on exercise has challenged this recommendation. To this end, a roundtable was convened by American College of Sports Medicine to distill the literature on the safety and efficacy of exercise training during and after adjuvant cancer therapy and to provide guidelines. The roundtable concluded that exercise training is safe during and after cancer treatments and results in improvements in physical functioning, quality of life, and cancer-related fatigue in several cancer survivor groups. Implications for disease outcomes and survival are still unknown. Nevertheless, the benefits to physical functioning and quality of life are sufficient for the recommendation that cancer survivors follow the 2008 Physical Activity Guidelines for Americans, with specific exercise programming adaptations based on disease and treatment-related adverse effects. The advice to "avoid inactivity," even in cancer patients with existing disease or undergoing difficult treatments, is likely helpful.

Predictors of follow-up exercise behavior 6 months after a randomized trial of exercise training during breast cancer chemotherapy.

PURPOSE: Exercise during breast cancer chemotherapy is beneficial but it needs to be maintained into survivorship to optimize long-term benefits. Here, we report the predictors of follow-up exercise behavior 6 months after a randomized exercise trial in breast cancer patients. METHODS: Breast cancer patients (N = 242) initiating adjuvant chemotherapy were randomly assigned to usual care (n = 82), supervised resistance exercise (n = 82), or supervised aerobic exercise (n = 78) for the duration of their chemotherapy. At baseline and postintervention, data were collected on demographic, medical, behavioral, fitness, psychosocial, and motivational variables. At 6-month follow-up, participants were mailed a questionnaire that assessed exercise behavior over the past 6 months and were categorized as either meeting both aerobic and resistance exercise guidelines, either exercise guideline, or neither exercise guideline. RESULTS: Two hundred one (83.1%) participants provided 6-month follow-up data with 85 (42.3%) meeting neither exercise guideline, 74 (36.8%) meeting either exercise guideline, and 42 (20.9%) meeting both exercise guidelines. In multivariate regression analysis, seven variables independently predicted the likelihood of meeting exercise guidelines at follow-up including higher pretrial exercise (beta = 0.23; P = 0.002), younger age (beta = -0.15; P = 0.028), breast conserving surgery (beta = 0.15; P = 0.033), strength improvements (beta = 0.15; P = 0.028), lower postintervention fatigue (beta = 0.13; P = 0.067), a more positive attitude (beta = 0.12; P = 0.086), and lower postintervention body mass index (beta = -0.11; P = 0.105). CONCLUSION: Exercise behavior 6 months after a randomized trial was predicted by a wide range of demographic, medical, behavioral, fitness, psychosocial, and motivational variables. These findings may help facilitate the uptake of exercise behavior during the transition from breast cancer patient to survivor.

Randomized controlled trial of resistance or aerobic exercise in men receiving radiation therapy for prostate cancer.

PURPOSE: Radiotherapy for prostate cancer (PCa) may cause unfavorable changes in fatigue, quality of life (QOL), and physical fitness. We report results from the Prostate Cancer Radiotherapy and Exercise Versus Normal Treatment study examining the effects of 24 weeks of resistance or aerobic training versus usual care on fatigue, QOL, physical fitness, body composition, prostate-specific antigen, testosterone, hemoglobin, and lipid levels in men with PCa receiving radiotherapy. PATIENTS AND METHODS: Between 2003 and 2006, we conducted a randomized controlled trial in Ottawa, Canada, where 121 PCa patients initiating radiotherapy with or without androgen deprivation therapy were randomly assigned to usual care (n = 41), resistance (n = 40), or aerobic exercise (n = 40) for 24 weeks. Our primary end point was fatigue assessed by the Functional Assessment of Cancer Therapy-Fatigue scale. RESULTS: The follow-up assessment rate for our primary end point of fatigue was 92.6%. Median adherence to prescribed exercise was 85.5%. Mixed-model repeated measures analyses indicated both resistance (P =.010) and aerobic exercise (P = .004) mitigated fatigue over the short term. Resistance exercise also produced longer-term improvements (P = .002). Compared with usual care, resistance training improved QOL (P = .015), aerobic fitness (P = .041), upper- (P < .001) and lower-body (P < .001) strength, and triglycerides (P = .036), while preventing an increase in body fat (P = .049). Aerobic training also improved fitness (P = .052). One serious adverse event occurred in the group that performed aerobic exercise. CONCLUSION: In the short term, both resistance and aerobic exercise mitigated fatigue in men with PCa receiving radiotherapy. Resistance exercise generated longer-term improvements and additional benefits for QOL, strength, triglycerides, and body fat.

Understanding breast cancer patients' preference for two types of exercise training during chemotherapy in an unblinded randomized controlled trial.

BACKGROUND: Patient preference for group assignment may affect outcomes in unblinded trials but few studies have attempted to understand such preferences. The purpose of the present study was to examine factors associated with breast cancer patients' preference for two types of exercise training during chemotherapy. METHODS: Breast cancer patients (N = 242) completed a battery of tests including a questionnaire that assessed patient preference and the theory of planned behavior (TPB) prior to being randomized to usual care, resistance exercise training (RET), or aerobic exercise training (AET). RESULTS: 99 (40.9%) participants preferred RET, 88 (36.4%) preferred AET, and 55 (22.7%) reported no preference. Past exercisers (p = 0.023), smokers (p = 0.004), and aerobically fitter participants (p = 0.005) were more likely to prefer RET. As hypothesized, participants that preferred AET had more favorable TPB beliefs about AET whereas participants that preferred RET had more favorable TPB beliefs about RET. In multivariate modeling, patient preference for RET versus AET was explained (R2 = .46; p < 0.001) by the difference in motivation for RET versus AET (beta = .56; p < 0.001), smoking status (beta = .13; p = 0.007), and aerobic fitness (beta = .12; p = 0.018). Motivational difference between RET versus AET, in turn, was explained (R2 = .48; p < 0.001) by differences in instrumental attitude (beta = .27; p < 0.001), affective attitude (beta = .25; p < 0.001), and perceived behavioral control (beta = .24; p < 0.001). CONCLUSION: Breast cancer patients' preference for RET versus AET during chemotherapy was predicted largely by a difference in motivation for each type of exercise which, in turn, was based on differences in their beliefs about the anticipated benefits, enjoyment, and difficulty of performing each type of exercise during chemotherapy. These findings may help explain patient preference effects in unblinded behavioral trials. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00115713.

Predictors of supervised exercise adherence during breast cancer chemotherapy.

PURPOSE: Exercise adherence is difficult during cancer treatments, but few studies have examined the predictors of such exercise. Here, we report the predictors of adherence to supervised exercise training during breast cancer chemotherapy. METHODS: Breast cancer patients (N = 242) initiating adjuvant chemotherapy in Edmonton, Ottawa, and Vancouver were randomly assigned to usual care (n = 82), supervised resistance exercise (n = 82), or supervised aerobic exercise (n = 78) for the duration of their chemotherapy. Baseline data on standard demographic, medical, behavioral, fitness, and psychosocial variables as well as motivational variables from the Theory of Planned Behavior were collected. Adherence was assessed by objective attendance records. RESULTS: Adherence to supervised exercise was 70.2%. Univariate analyses indicated significant or borderline significant associations between exercise adherence and location/center (r = 0.30; P < 0.001), V[spacing dot above]O2peak (r = 0.21; P = 0.008), muscular strength (r = 0.21; P = 0.008), percent body fat (r = -0.21; P = 0.012), disease stage (r = 0.17; P = 0.031), education (r = 0.15; P = 0.053), depression (r = -0.14; P = 0.073), and smoking (r = -0.14; P = 0.081). In multivariate analysis, location/center (beta = 0.28; P = 0.001), V[spacing dot above]O2peak ([beta] = 0.19; P = 0.016), disease stage (beta = 0.18; P = 0.015), and depression (beta = -0.16; P = 0.033) remained significant and explained 21% of the variance in exercise adherence. Participants in Vancouver, with higher aerobic fitness, more advanced disease stage, and lower depression, achieved better adherence. CONCLUSION: Adherence to supervised exercise training was predicted by unique aspects of the location/center, disease stage, aerobic fitness, and depression but not motivational variables. Location/center in our trial may have been a proxy for the amount of one-on-one attention received during supervised exercise. These findings may have implications for improving adherence during breast cancer chemotherapy.

Barriers to supervised exercise training in a randomized controlled trial of breast cancer patients receiving chemotherapy.

BACKGROUND: Exercise adherence is a challenge for breast cancer patients receiving chemotherapy but few studies have identified the key barriers. PURPOSE: In this paper, we report the barriers to supervised exercise in breast cancer patients participating in a randomized controlled trial. METHODS: Breast cancer patients initiating adjuvant chemotherapy (N = 242) were randomly assigned to usual care (n = 82) or supervised resistance (n = 82) or aerobic (n = 78) exercise. Participants randomized to the two exercise groups (n = 160) were asked to provide a reason for each missed exercise session. RESULTS: The two exercise groups attended 70.2% (5,495/7,829) of their supervised exercise sessions and provided a reason for missing 89.5% (2,090/2,334) of their unattended sessions. The 2,090 reasons represented 36 different barriers. Feeling sick (12%), fatigue (11%), loss of interest (9%), vacation (7%), and nausea/vomiting (5%) accounted for the most missed exercise sessions. Disease/treatment-related barriers (19 of the 36 barriers) accounted for 53% (1,102/2,090) of all missed exercise sessions. Demographic and medical variables did not predict the types of exercise barriers reported. CONCLUSIONS: Barriers to supervised exercise in breast cancer patients receiving chemotherapy are varied but over half can be directly attributed to the disease and its treatments. Behavioral support programs need to focus on strategies to maintain exercise in the face of difficult treatment side effects.

Moderators of the effects of exercise training in breast cancer patients receiving chemotherapy: a randomized controlled trial.

BACKGROUND: Exercise training improves supportive care outcomes in patients with breast cancer who are receiving adjuvant therapy, but the responses are heterogeneous. In this study, the authors examined personal and clinical factors that may predict exercise training responses. METHODS: Breast cancer patients who were initiating adjuvant chemotherapy (N=242) were assigned randomly to receive usual care (UC) (n=82), resistance exercise training (RET) (n=82), or aerobic exercise training (AET) (n=78) for the duration of chemotherapy. Endpoints were quality of life (QoL), aerobic fitness, muscular strength, lean body mass, and body fat. Moderators were patient preference for group assignment, marital status, age, disease stage, and chemotherapy regimen. RESULTS: Adjusted linear mixed-model analyses demonstrated that patient preference moderated QoL response (P= .005). Patients who preferred RET improved QoL when they were assigned to receive RET compared with UC (mean difference, 16.5; 95% confidence interval [95% CI], 4.3-28.7; P= .008) or AET (mean difference, 11; 95% CI, -1.1-23.4; P= .076). Patients who had no preference had improved QoL when they were assigned to receive AET compared with RET (mean difference, 23; 95% CI, 4.9-41; P= .014). Marital status also moderated QoL response (P= .026), age moderated aerobic fitness response (P= .029), chemotherapy regimen moderated strength gain (P= .009), and disease stage moderated both lean body mass gain (P< .001) and fat loss (P= .059). Unmarried, younger patients who were receiving nontaxane-based therapies and had more advanced disease stage experienced better outcomes. The findings were not explained by differences in adherence. CONCLUSIONS: Patient preference, demographic variables, and medical variables moderated the effects of exercise training in breast cancer patients who were receiving chemotherapy. If replicated, these results may inform clinical practice.

Six-month follow-up of patient-rated outcomes in a randomized controlled trial of exercise training during breast cancer chemotherapy.

BACKGROUND: Few exercise trials in cancer patients have reported longer-term follow-up. Here, we report a 6-month follow-up of exercise behavior and patient-rated outcomes from an exercise trial in breast cancer patients. METHODS: Breast cancer patients initiating adjuvant chemotherapy (n = 242) were randomly assigned to usual care (n = 82), resistance exercise training (RET; n = 82), or aerobic exercise training (AET; n = 78) for the duration of their chemotherapy. At 6-month follow-up, participants were mailed a questionnaire that assessed quality of life, self-esteem, fatigue, anxiety, depression, and exercise behavior. RESULTS: Two hundred one (83.1%) participants provided 6-month follow-up data. Adjusted linear mixed-model analyses showed that, at 6-month follow-up, the RET group reported higher self-esteem [adjusted mean difference, 1.6; 95% confidence interval (95% CI), 0.1-3.2; P = 0.032] and the AET group reported lower anxiety (adjusted mean difference, -4.7; 95% CI, -0.0 to -9.3; P = 0.049) compared with the usual care group. Moreover, compared with participants reporting no regular exercise during the follow-up period, those reporting regular aerobic and resistance exercise also reported better patient-rated outcomes, including quality of life (adjusted mean difference, 9.5; 95% CI, 1.2-17.8; P = 0.025). CONCLUSIONS: Improvements in self-esteem observed with RET during breast cancer chemotherapy were maintained at 6-month follow-up whereas reductions in anxiety not observed with AET during breast cancer chemotherapy emerged at 6-month follow-up. Moreover, adopting a combined aerobic and resistance exercise program after breast cancer chemotherapy was associated with further improvements in patient-rated outcomes. Exercise training during breast cancer chemotherapy may result in some longer-term and late effects for selected patient-rated outcomes.

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.